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    Getting into mod/con business (127 Posts)

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    Getting into mod/con business

    Good afternoon to all. I am (finally) considering getting into the mod/con installation and service business. Obviously, manufacturer's training is a must. I have a few basic questions (I am sure that many more will follow).
    1. The bulk of my work is in Queens and Nassau county. Which makes and models have readily accessible replacement parts in this area? I can't have a situation where parts go bad and it takes a few days or more to get replacement parts.
    2. Which mod cons are best in terms of durability, ease of installation and service, customer service, warranty length and coverage, ease in getting warranty honored, etc?
    This post was edited by an admin on July 1, 2014 3:31 PM.
  • Snowmelt Snowmelt @ 5:16 PM
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    Go with

    What ever your supply house has. Weil McClain , peerless , Utica, crown, navian triangler tube, veisman .
  • Zman Zman @ 8:41 PM
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    Triangle Tube

    I like the Triangle Tube boilers.The fire tube exchanger is a workhorse They have good training and support. The warrantee is an easy process. They make a service parts kit that works for all models.
    I am not in New York.
  • Mad Dog Mad Dog @ 8:29 PM
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    Triangle Tube............

    Great product, parts readily avail. reps are out to help you. Mad Dog
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    I haven't had much time to give this topic much thought. As soon as I have time to clear my head,I will come back with some more intelligent questions. Just a few basic questions.
    1. I have read online all sorts of horror stories. Various parts breaking resulting in expensive repairs and long delays in getting heat back on. Repeat lockouts. Savings not being as high as advertised. Warrenty problems. Etc. Are these stories the norm are the exception? Are they result of manufacturing defects or poor installations?
    2. What water quality issues are relevant to mod/cons? Hard water,acidic water etc?
    3. Some of the areas that I service have unpredictable gas pressures (particularly during extreme cold spells). What effect will that have on the mod/cons?
    4. Does the condensing factor result in significant savings on hi temp systems? I understand that the modulation factor will result in significant savings on all systems. An outdoor reset will bring the condensing factor into play during the warmer parts of the heating system. However, are those savings enough to justify the extra expense of condensing boilers? Would modulation without condensing be a better option on hi temp systems?
  • Snowmelt Snowmelt @ 11:17 PM
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    Before we go further

    What you have to do is go to a few classes, I am in field 16 years in June, 11 by myself and every day I learn something new.
    With that being said I would go to taco websight and go to there webinars........
    Or go to a supply house and take condensing boil classes

    Just way to much info to be learn from writing back and forth.
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    If you read the original post, you will see that I referenced the need for training. That is a given. The drawback of manufacturer's training is that everyone is trying to push their product. I am looking for independent and unbiased opinions from the experts out in the field. Nuff said.
  • Rich Rich @ 10:55 AM
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    Taco training

    is the best you will receive without them pushing their product , yes they will tell you how their product can help in certain situations but  I assure you that it is APPLICATION based in whole . It si very reasonably priced and they will make hotel accomodations for you and ground transportation is provided . I hate manufacturer training for probably the same reasons as you and this is where you want to go . Try their site also at the Flopro neighborhood and go to Taco University , you will gain real insight to fluid based systems application without a manufacturer telling you why their product is the best . Have no idea what your current knowledge is but even for guys that know a bit you will gain much knowledge . 
    You didn't get what you didn't pay for and it will never be what you thought it would
  • Harvey Ramer Harvey Ramer @ 7:13 AM
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    4 Big ones that will kill a ModCon

    Short cycling.
    Improper venting.
    Inadequate flow through the heat exchanger.
    Poor water quality.

    There are obviously some more pitfalls, but most of the failures I see are a result of one of the above.


    PS. I also am a fan of Triangle Tube and the Fire Tube HX.
  • Chris Chris @ 7:55 AM
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    Steam Dr

    I'm in your market and could arrange for a nice sit down with Viessmann as soon as this upcoming week. I know that the VitoMobile will be touring your market the week of 7/14. Factory is in RI and all training is free. The next round of classed for Vitodens is at the end of the month. Just click on the link for registration and seminar schedule.

    Viessmann is serviced in your market by a Factory Rep not a rep agency so your relationship is direct with the factory and the wholesaler. Generally, Viessmann isn't sold on the "sales pitch" but rather from the technical side. Its a system approach not just a boiler approach. Feel free to drop me an email if you'd like.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
    This post was edited by an admin on July 4, 2014 8:01 AM.
  • hot rod hot rod @ 8:06 AM
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    here is a course

    that will be right up your alley. Roy will present a generic and in-depth mod con class. he does a great job explaining combustion in everyman language. Online courses make it very easy to learn.

    Plenty of other great classes at this school also.
  • SWEI SWEI @ 11:41 AM
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    Selling & installing mod/con boilers

    you are about to embark on a relationship with a manufacturer that will last a decade or more.  Even if you decide to change horses in six months, you will still own the boilers you installed before you changed your mind.  You are smart to be asking about this before you jump into something.

    Like several others here, I have had great experiences with both Triangle Tube and Viessmann.  Quality products, quality training, and they will be there for you when/if the going gets tough.  Rinnai sells a good product and has comprehensive training, but the price makes them a tough sell, at least in our market.  Lochinvar has very flexible onboard controls but has become somewhat of a commodity around here.

    Modern modulating/condensing boilers only perform as advertised when they are properly applied, sized, installed, and commissioned.  They do not tolerate fools. In a sane world, these products would only be sold to qualified installers.  The unfortunate reality of our distribution system here in the US will quickly give any manufacturer who tries that the kiss of death.  The better manufacturers provide incentives to their trained installers (sometimes in the form of extended warranties) to try and give them an edge over the trunk slammers who buy their products out of distribution.
    This post was edited by an admin on July 4, 2014 3:27 PM.
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    Basic question

    All advise has been well taken. This is a business that I do not want to jump into unless I am 110% confident of my competence and 110% confident t that I am giving the customer the best bang for the buck.
    I really need to backtrack to a more basic question. Are mod/cons worth it? After factoring in the additional installation cost, the additional maintenance costs, the additional repair costs, the shorter boiler lifespan, possible water treatment costs etc, are mod/cons are worthwhile investment?
    This is not meant as an attack question. This is a "I really need to know " question. This is the question that all of my customers will be asking me. I cant install these boilers (or any other product) unless I am sure that the answer is YES!
    Most of my customers are in residential, older, uninsulated homes with heat loads maxing out around 200 mbtu.
    All opinions, advise and insights are greatly appreciated.
  • Snowmelt Snowmelt @ 10:38 AM
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    Here is what I think your looking for.........

    From your statement, if your home is uninsulated, dollar for dollar, dime for dime, apple to Apple, for investment purposes your way better off if you upgrade the insulation, install better windows, just add outdoor reset and either a bumble bee taco or a delta tee circulator. With doing these things you mostly save 15% as low to and as high as 25%.

    So answer would be no.

    On other hand, if a costumer already or going to do the upgrade and same time replace the boiler. The chimney has to be relined anyway because it has cracks or they switching from oil to gas.
    The answer would be yes it's worth it.
    If you give me a private email I will give you my number, I see your in NY which is just around the corner from me.
  • SWEI SWEI @ 10:39 AM
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    Do the math

    because it's different for each region and even for individual utilities.  Out here NG currently costs under 70 cents per therm including fees and taxes.  With our short heating season and assuming a 15 year life on the mod/con, it's a tough sell for smaller houses -- but a no-brainer for commercial projects.  OTOH for customers on LPG, even a 60k design day load usually justifies one.
  • bc3510 bc3510 @ 1:16 PM
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    The math

    Here in the Northeast a "typical" 2000 square foot house might use 1100 therms per year at an overall efficiency of 70% (with typical 80% equipment).

    At a total gas cost of $1.20, the yearly expenditure is $1320.

    If you install the mod/con and have sufficient radiation to keep the return water temperature sufficiently low (no easy task with existing fin tube), you might get an overall efficiency of 90% (but I'm skeptical of that figure).

    The difference between 70% and 90% is 28%,

    So, the total gas usage would drop to 792 therms.

    Savings @ $1.20: $369. per year.

    Now, weigh that savings against the additional purchase price of the mod/con, the additional installation costs for the mod/con, and the annual maintenance on the mod/con.

    You'll also note that if the mod/con suffers a failure of any of its expensive parts in the 10 years that the customer owns it, he's immediately underwater from a cost standpoint.

    The sad truth about this equipment is easily discernible if you run the numbers.
  • NYplumber NYplumber @ 3:48 PM
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    Way Off

    You are WAY off the mark. The difference i$ not proportional to the efficiency rating. Designed and implemented correctly there is more savings. Installing a mod con is not necessarily done for payback, its also for comfort, and for some its about the environment.
  • bc3510 bc3510 @ 3:57 PM
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    The difference

    By definition, the difference in dollars is directly proportional to the OVERALL system efficiency rating.

    There is no other way to calculate it.

    The only argument regarding dollars is whether the stated efficiency ratings are typical of the installed equipment.

    I understand that you wish to believe otherwise, but you can't argue with the physics.

    If you want to make an argument that the mod-con is more "comfortable", have at it. I believe the question concerned the cost of ownership. Only the homeowner can determine if the additional cost of the mod-con is worth the expense for them.
    This post was edited by an admin on July 7, 2014 4:27 PM.
  • Chris Chris @ 1:47 PM
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    There's A Lot

    Of misconception here. Let's start with the let's compare AFUE to AFUE to come up with savings. Simply cannot do that alone. I know its a number that can be easily plugged into a formula but its also an unfair equation.

    When we talk about comparing a traditional pin-style boiler vs a condensing boiler we aren't being fair with our terminology. We should be comparing a FIXED Rate boiler vs a modulating boiler. Similar to when we compare a fixed speed pump to a variable speed pump.

    The other factor that is always left when I see these AFUE equations and the one rarely talked about is condensate. We know the Fixed Rate Boiler isn't able to capture condensate. Heck we protect them from it. So in a condensing boiler, for every one gallon of condensate we do capture (roughly 8,000 btu/hr) we've turned lost energy (btu/hr) from the fixed rate boiler to usable engery that the consumer paid for. This has to be a factor when comparing.

    Modulation Rate - While that fixed rate boiler is stomping on the gas peddle in late Oct, Nov,Dec then again in Mar, Apr our condensing boiler is just cruising along like as if you turned on cruise control in your car. It's reacting to the hills. As we we head up one she gives us more btu/hr as we coast down, she lighten's up on the btu/hr. Where's that in the AFUE equation?

    Now onto the maintenance argument...Why is it that as consumers we're ok with heading down to our local jiffy lubes or fav local garage 4 times a year for an oil change but as soon as the word preventative maintenance is used with a condensing boiler , the sky opens up and falls on us? Come on, the consumer wants longevity and that comes at the same price tag as his 4 oil changes a year. Heck, people throw cars out like they are candy for god sake. - The consumer didn't create this argument. The trade created it against themselves and now the consumer reads it and then uses against them! Its the trade shooting themselves in the foot!

    I could go on and on with this subject, but let's digest some of this for a bit...Happy Monday!
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • bc3510 bc3510 @ 2:07 PM
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    In my analysis, I was comparing a fixed rate boiler with a mod-con. I made the assumption that the fixed rate boiler could achieve an overall efficiency of 70% if it was brand new and not oversized. I also made an assumption that the mod-con could achieve an overall efficiency of 90% if it is setup properly.

    The only argument you can have is whether the two percentages listed above are valid. If you accept those percentages, the savings for a 2000 square foot house is $369. per year.

    There isn't any argument that the mod-con needs more maintenance as compared to the 80% unit. That's a given. You simply estimate that cost and compare it to your savings that you get from the mod-con.

    If the maintenance in this example is $300. per year, you'd be $69. ahead at the end of the year. Note, however, that the $69. savings per year doesn't have a prayer of paying the amortization of the much higher purchase and installation cost of the mod-con.

    Of course, this makes the assumption that the mod-con does not need ANY repairs that are greater than $690. for it's entire estimated 10 year lifespan. I think we both know how unrealistic that is.
    This post was edited by an admin on July 7, 2014 2:10 PM.
  • Chris Chris @ 2:12 PM
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    So What Is

    70% of 100,00 btu/hr = 70,000 btu/hr used
    90% of 30,000 btu/hr = 27,000 btu/hr used

    So where does that extra gap of 43,000 btu/hr you used an I didn't come into the equation?
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • bc3510 bc3510 @ 2:17 PM
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    I believe you're a bit confused as to how these calculations are done.

    It takes a certain amount of BTU's to heat a house. You simply determine the efficiency of the equipment that you have and you then get the total energy required.

    You do not get to reduce the heat requirement down to 30,000 BTUH for the mod-con and compare it to 100,000 BTUH for the conventional equipment...........LOL.
    This post was edited by an admin on July 7, 2014 2:18 PM.
  • Chris Chris @ 2:19 PM
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    Sure I do

    The structures heat loss changes every day. I'm a smart modulating boiler I can adapt to it. You're a fixed rate boiler - You don't stop firing until you make high limit.

    Does all your created energy (btu/hr) go on a coffee break and wait for the horn to blow to get back to work?
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
    This post was edited by an admin on July 7, 2014 2:22 PM.
  • bc3510 bc3510 @ 2:23 PM
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    coffee break

    Of course it goes on a coffee break.

    All conventional equipment is on "coffee break" for most of the year. The duty cycle of conventional equipment is woefully small. Only on the design day, and ONLY if the equipment is sized perfectly, will the conventional equipment run at 100% duty cycle. In reality, it never happens.

    The mod-con is also on a "modified coffee break". It has the ability to downfire itself and never shutdown for a good portion of the heating season. Sadly, however, even with its 5:1 turndown ratio, most of them will still shutdown in the shoulder months. This is the reason that they cannot achieve 95% overall efficiency (and one that is usually ignored by most).
    This post was edited by an admin on July 7, 2014 2:27 PM.
  • Chris Chris @ 2:28 PM
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    It Could Be Said

    That that dumb fixed speed primary/boiler pump is the reason for short cycling not the actual condensing boiler itself. Could also be said that's the reason most condensing boiler don't condense.

    There is no Coffee Break.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • JStar JStar @ 5:40 PM
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    Let's say that the average mod/con does only save $300-400 per year. The cost of my mod/con install versus a conventional boiler is maybe $2500. So the payback on cost difference is about 6.5 years. That seems VERY smart to me. Plus, each future install will be cheaper than the original one; venting and piping being salvaged for the next boiler.

    Combustion efficiency may only be 20% better, but modulating can add another 30-50% in fuel usage reduction.
  • bc3510 bc3510 @ 6:47 PM
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    The mod/con can save 50% in fuel if the current system efficiency is 63% and the final mod/con efficiency is 95%.

    This scenario is quite likely in an old oil boiler, way oversized, without the benefits of maintenance.

    However, the comparison that was originally portrayed was between a modern 80% unit and the mod/con.

    It is a physical impossibility for the mod/con to save 50% in fuel in that comparison.

    Each person must determine for themselves whether the mod/con is valuable to them. However, they cannot save sufficient dollars to pay for the purchase and maintenance of the mod/con when compared to a modern 80% system. In your analysis, above, the annual maintenance and repairs for the mod/con are missing from the cost calculations.

    Note that the original premise was 1100 therms @ $1.20 per therm. If you raise that figure for a larger house, the calculation changes and the mod/con becomes more attractive.
    This post was edited by an admin on July 7, 2014 6:51 PM.
  • JStar JStar @ 6:52 PM
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    I lose you when you say that a mod/con can't reduce fuel consumption by 50%. How is that impossible? I can turn the boiler off completely, and it will save 100% fuel.
  • bc3510 bc3510 @ 7:10 PM
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    If a boiler can convert every last molecule of gas into heat and distribute it to the radiation, we have a system that operates at 100% efficiency.

    We know that no system can do that.

    Every system loses some heat to the exhaust and some heat to spaces such as the basement and the exterior walls where the heat cannot be utilized for comfort.

    We estimate that a properly functioning mod/con can effectively transfer 90% of all the fuel consumed to the heated space. That's a daunting task, but it can be done. Note, however, that it is not likely to be done with high temperature radiation.

    Now we take a look at conventional equipment. It has a combustion efficiency of 80%. This means that 20% of the fuel consumed goes right up the stack. We also know that the unit cannot operate below 135F, and we also know that it is oversized for the heat load for 99% of its operation. These two parameters combine to lower the system efficiency of the conventional equipment well below 80%. The question is simply, "How much below?".

    I made an assumption that a new conventional 80% boiler, with some adjustments to the water temperatures and possibly with the use of outdoor reset and primary secondary piping, can achieve a system efficiency of 70%. It converts 70% of the fuel consumed into heat for the space. 30% is lost to the exhaust and to unheated spaces.

    The comparison between the two systems is therefore 90% versus 70%. The difference in fuel is the ratio of 90/70. This equates to 28%.

    You cannot save MORE than 28% unless the system efficiency of the conventional equipment is LESS than 70% or the system efficiency of the mod/con is MORE than 90%.

    Each of these scenarios is possible under certain circumstances. But, you must have one (or both) of these scenarios present if you wish to save more than 28% on fuel.

    It is absolutely possible to get a mod/con to perform at 95%, but it usually isn't on a retrofit. It is also absolutely possible for conventional equipment to operate at 60% but it usually isn't on a new installation, properly sized, with some additional controls to reduce supply temperature to the greatest degree possible.

    If we compare the 95% mod-con to the 60% conventional installation, we find a difference of 58% in fuel.

    If I were a contractor and wanted to sell a mod/con, I'd simply look at the hugely oversized boiler operating at 180/160 24/7/365 and I could just about guarantee the homeowner that he'll save 50% on fuel (provided that I found enough radiation in the house to operate the system at lower supply temperatures).

    But, realize, you're comparing apples and oranges............that's all.
  • Chris Chris @ 8:10 PM
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    I so want

    To get into this debate more but you're stuck on AFUE. How many conventional fixed rate boilers do you know that run 140 supply 120 return constantly? The test is flawed which in turn makes your argument flawed.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • bc3510 bc3510 @ 8:28 PM
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    There isn't any debate.

    AFUE is the standard of measure.

    The only discussion is what you believe the AFUE to be for a specific installation. I explained that this variable is a bit subjective and conventional equipment could be as low as 50% if all of the worst offenders are present.

    Any other discussion regarding other variables will affect the AFUE, but, at the end of the day, this is the parameter used to calculate the heat delivered to the building.

    You use the oil truck or the gas meter to determine the total amount of fuel burned by the equipment.
  • NYplumber NYplumber @ 1:15 AM
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    Dry vs Wet

    I have seen a graph of dry base boilers vs wet base boilers that illustrated time on one axis and efficiency on the other axis. The wet base power burner boiler achieved higher efficiency quicker due to drying up the flu at a faster rate. Add that thought when comparing conventional dry base boilers to condensing equipment.
  • Gordy Gordy @ 9:29 PM
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    The Big V

    I wonder how Viessmann can tote 108% efficiency with their Mod/Cons with return water temps below 90ish Hmmm.

    You really have to think about the modulation, smart boiler/system pumping, system, and boiler loop deltas, RWT, Radiation being used. Those are all huge components of over all efficiencies. I say OVER ALL efficiency because AFUE just does not apply its a half a$$ benchmark that people try to apply to everything in the boiler line up. Remember the goal is to make the SYSTEM more efficient not just the boiler. Talk seasonal efficiencies.

    Im just rying to get through the new math.
  • bc3510 bc3510 @ 10:57 PM
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    108% efficiency

    That's the new math where the system can actually produce 8% more heat than the amount of BTU's in the fuel.

    Fantastic for Viessman if they can get a few contractors to believe it.

    With regard to AFUE, I quote the following statement which is the definition of the term:

    " The AFUE differs from the true 'thermal efficiency' in that it is not a steady-state, peak measure of conversion efficiency, but instead attempts to represent the actual, season-long, average efficiency of that piece of equipment, including the operating transients.[1] It is a dimensionless ratio of useful energy output to energy input, expressed as a percentage. For example, a 90% AFUE for a gas furnace means it outputs 90 BTUs of useful heating for every 100 BTUs of Natural Gas input (where the rest may be wasted heat in the exhaust)."

    My references above are the precise definition of AFUE. However, this does in no way reference the current METHOD utilized to determine AFUE and slap it on the side of the boiler. I'm speaking of the actual AFUE, which is not easily determined for a system.

    The actual AFUE is the only way of comparing the efficiency of one system to another system.
    This post was edited by an admin on July 7, 2014 11:03 PM.
  • Gordy Gordy @ 6:21 AM
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    Second to last sentence

    In my last post I meant to type "seasonal SYSTEM efficiency". Because in the end with any boiler it is just one component of the whole hydronics system. But most mod/cons have built in components that enhance the total system.

    Thats why AFUE needs to be dropped from this debate as Chris stated. The systen plays a big tole in how much actual savings will be achieved by any boiler.
    This post was edited by an admin on July 8, 2014 6:22 AM.
  • Chris Chris @ 8:37 AM
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    Home Run

    Gordy hit the home run in the bottom of the ninth on a 2 strike count for the win. Here's the Viessmann chart Gordy refer's to.

    BC, let me tell you a little about Viessmann. If anything they are conservative in what they publish. They always have been.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • bc3510 bc3510 @ 11:27 PM
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    You posted a chart provided by the manufacturer which shows the BOILER efficiency at various supply water temperatures.

    You do understand that this chart doesn't at all represent the SYSTEM efficiency (AFUE)?

    I know you desperately want to cling to the data that Viessmann provides for you, but you really ought to understand what you post.

    Also, nothing on that chart has a prayer of 100%, much less 108%,.
  • bc3510 bc3510 @ 9:55 PM
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    I provided the definition of AFUE.

    If you read it and understand it, it is the only way to compare two different systems. Note that the AFUE calculated by the boiler manufacturer isn't what I'm referring to.

    The total system efficiency of one system as compared to another system is the method of comparison. This, by definition, is AFUE and it is very difficult to calculate accurately.
  • bc3510 bc3510 @ 10:12 PM
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    Apparently, Gordy, you didn't bother to read the definition of AFUE.

    If you did, you might realize that the "system efficiency" that you refer to is exactly what the "AFUE" is.
  • Rich Rich @ 10:55 AM
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    Where from ?
    You didn't get what you didn't pay for and it will never be what you thought it would
  • RobG RobG @ 1:58 PM
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    This debate is proceeding from a gentleman who believes that using a water heater with a flat plate HE and a stainless pump for his heat and domestic hot water is the best way to go because a modcon or even a cast iron or steel boiler would be a rip-off. Who needs an H-Stamp? Boilers were only created to rip of the consumer! It's not like that continuously running water heater will scale up at the bottom plummeting the efficiency because of the constant fresh make up water. He's an engineer, he knows best! Why don't you guys just accept that he is smarter than everyone else? I do.  :0)

    To the original poster. Yes, there is a market for modcon's. Just make sure to do your research. Find a wholesaler and rep firm that are good to deal with and get the technical training. If properly maintained they will pay for themselves and then some. Just get comfortable with the the product. I had a rep take me out to a couple of light commercial jobs to see the installations to get and idea of the different scenarios (they were just boiler rooms that he had access to). Those were the days of the Pulse combustion boilers. I'm glad the industry has worked out the bugs :) 

    Good luck, do your homework and you will do well.


  • bc3510 bc3510 @ 10:28 PM
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    ..........holding off the conclusion regarding my hot water heater installation. I am fully aware that this machine is way out of the normal bounds for a hot water heater and it might not have the durability that I expect (six years).

    I'll post all the details about it and I'll post it's performance as compared to the existing oil fired equipment. I'll have a good baseline for the oil fired equipment to make a decent estimation of the system efficiency.

    Then, we'll compare the system efficiency of the hot water heater.

    Understand the installed cost for the hot water heater is just about $2.2K, so, even if it is an abject failure, there isn't any great loss.

    Furthermore, it's going to be installed in parallel to the existing oil boiler so if it fails miserably, I have a backup.

    One thing is certain: It has no fancy computer controls and no exotic heat exchanger and no expensive components that will leave me without heat for several weeks.

    Also, you made a critical error in the analysis of the makeup water causing excessive scale buildup at the bottom of the tank. The only makeup water is from domestic hot water use............just like any other hot water heater. The domestic heating is done with a loop through the heat exchanger and doesn't contribute anything to the scale accumulation.
  • SWEI SWEI @ 4:37 PM
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    Real-world savings

    > I'm speaking of the actual AFUE, which is not easily determined for a system.

    > The actual AFUE is the only way of comparing the efficiency of one system to another system

    AFUE is a computed value, and as many have mentioned here, not a particularly useful one.  The real-world annual energy savings is quite simple to compute, but it does require a couple of months of winter fuel usage.  Calculate the number of BTUs consumed and divide those by the number of heating degree days and you get something resembling the truth.  In my world the truth is a savings of 40% or better using the math I just described.  We tell customers to expect "at least 30%" and have yet to miss our mark.  When replacing older, oversized, improperly controlled systems we frequently see savings as high as 70%.
  • Robert O'Brien Robert O'Brien @ 5:58 PM
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    Got this email in the spring

    I finally had a chance to calculate the savings after switching from oil to gas the other day. With the new system you installed I saved 56% compared to the previous year. Even better, I got my gas bill today and after finally taking a meter reading (they have been estimating my usage since February) they just credited my account $349. So the saving ends up being a bit better than 56% - I didn't update my calculations yet.

    I just thought I would pass that info along as you asked the last time you were here and I think that the savings are very impressive.

    Thanks once again for all of your help with the system.


    This isn't a mod/con,it's an 85% CI gas boiler. It replaced an old oil steel boiler and John Wood oil fired HWH.It's also not corrected for degree days and 2013-2014 winter was much colder than the prior year,so the savings is well over 60% of which only 37% can be attributed to the fuel cost differential.
  • bc3510 bc3510 @ 10:08 PM
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    real world savings

    There is no dispute on saving 40%. I already explained how you would save it.

    If the mod-con has an AFUE of 90% and the conventional system has an AFUE of 64%, you get exactly your claimed 40% savings.

    Note, however, that the 64% system efficiency of the equipment that you are replacing most certainly is not the latest conventional equipment with 80% combustion efficiency.

    I already stated that a brand spanking new 80% system would have a typical AFUE of 70% and you'd "only" save 28% on fuel.

    The 28% equates to $300. per year for a typical 2000 square foot house.

    You all wish to compare apples and oranges because it serves your purpose.

    This post was edited by an admin on July 8, 2014 10:10 PM.
  • R Mannino R Mannino @ 7:32 PM
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    Happy Customers

    are great! With or without Mod/Cons there is so much room for improvement there is no need to reinvent the wheel. Do Mod/ Cons work, yes they will save 50% percent over existing gas equipment even with a less than perfect application. But I only know what I am told by the customers, so what do I know?

    You forgot the before shot chief.
  • bc3510 bc3510 @ 9:53 PM
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    Nice comparison

    You show a before shot of ancient oil fired equipment and an after shot of new gas fired equipment.

    Then you are pleased with a 50% reduction in total fuel costs.

    You believe this is a fair comparison?
  • R Mannino R Mannino @ 4:12 PM
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    The Customers

    just want to spend less for heat and hot water. Some don't worry about the ride just as long as they arrive at the destination (Mercedes or Prius). As far as fuel change it's a no brainer, if available. We have had customers save 50% in dollars from gas to mod con, it's not an illusion..........really.
  • Gordy Gordy @ 7:52 PM
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    The new math

    I was alluding to was not from boiler manufacturers. It was some previous posts. A well designed envelope with tight radiant tube spacing, and lower room set point can achieve those efficiencies....easily.

    Most on the wall do more than change a boiler out. They also try to hone the total system with in budget restraints, and existing infrastructure. Remember most of the time the boiler was way oversized. If the installer is lucky, and the owner upgraded the envelope then the radiation will be oversized IF sized correctly for the old envelope. Those two things are huge compliments to savings of a correctly installed, and sized boiler. throw in modulation, lower water temps ODR. smart circ technology it gets better.

    Sorry BC I just can not agree with you.
  • bc3510 bc3510 @ 9:47 PM
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    Don't agree?

    What exactly do you not agree with?

    You don't agree that the calculation for efficiency for one system as compared to another system is based on the AFUE?

    Or you don't agree that a mod-con's efficiency is typically 90%?

    Or you don't agree that a new conventional system efficiency is typically 70%?

    Anybody can state that they don't agree. But, the devil is in the details and you have provided none.
    This post was edited by an admin on July 8, 2014 9:49 PM.
  • SWEI SWEI @ 10:35 PM
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    > You don't agree that the calculation for efficiency for one system as compared to another system is based on the AFUE?

    > Or you don't agree that a mod-con's efficiency is typically 90%?

    > Or you don't agree that a new conventional system efficiency is typically 70%?
    This post was edited by an admin on July 8, 2014 10:41 PM.
  • bc3510 bc3510 @ 10:37 PM
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    Well, sorry, you're absolutely incorrect.

    As far as the stated efficiencies, feel free to substitute your own values. Maybe you believe the mod-con is at 95%? Maybe you believe the conventional equipment is at 50%, even though it has a combustion efficiency of 80%?

    You're free to substitute any figures you wish and they will determine your fuel savings.
  • SWEI SWEI @ 10:40 PM
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    I'm quite satisfied with BTUs per degree-day (along with a per-square-foot modifier with which to compare disparate buildings.)
  • Gordy Gordy @ 10:53 PM
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    As Kurt said earlier the true formula for an equal comparison to any home any systems fuel usage, and performance.

    BTUS per HDD per SF. Very easy to calculate, and a very accurate indicator of how a total system including the envelope is performing.

    You can calc it daily, hourly, monthly, yearly. before an install, and after an install.

    you can compare your usage to your neighbors usage even though their set point is 72*, and yours is 65*.. It does not care if its 20* or -20*. It does not care if they have a forced air furnace, and you have whatever...In my opinion it is really the only true total system perfrmance bench mark worthy of any salt.

    If you use it before, and after a heating system overhaul its going to give you the most accurate savings percentage.

    Edit: No assumptions needed. Just the facts.
    This post was edited by an admin on July 8, 2014 11:07 PM.
  • bc3510 bc3510 @ 11:13 PM
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    BTU per HDD

    I fully agree that you can calculate the BTU's per HDD. If you have the figure from the previous system, you can definitely compare it to the new system using this calculation.

    Note, however, that this can only be done AFTER the new system is installed.

    Also note that you can determine the difference between the AFUE for the old system and the new system by this calculation AFTER the new system is installed.

    None of these calculations affect the previous discussion regarding AFUE and the fuel savings resulting from two systems with different AFUE's.

    What you cannot do with your calculation is to determine the fuel savings between your new mod-con and new conventional equipment. This is because you did not install any conventional equipment to make that calculation.

    It is in your collective best interests to ignore the AFUE for new conventional equipment and you continue to do so.
  • Gordy Gordy @ 11:43 PM
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    Having a hard time

    Figuring out your beef?

    Is it you dont believe boilers achieve stated performance?

    You think mod/cons are a waste of money?

    Most everyone is pretty comfortable with their understanding of how the savings can be reeped by any type of installed new boiler. So where are you going with all this exactly?
  • bc3510 bc3510 @ 11:47 PM
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    Having a hard time

    I'm the one having the hard time figuring out why you're arguing about a fairly standard calculation?

    I don't have any objection to you installing mod-cons to your heart's content.

    Just don't compare the efficiency of your new mod-con with the efficiency of new 80% equipment and claim you can get 50% fuel savings. It isn't happening in your lifetime.

    If you go back and look at the question by the OP, he asked whether he could be certain that a mod-con would be the best value for his customers after the purchase costs, installation costs, maintenance and repair costs are compared to conventional equipment.

    I responded that a new conventional system, properly sized with outdoor reset and reduced supply temperatures will achieve an AFUE of about 70%. This gives the mod-con an advantage of 26% fuel savings. That amount, in dollars, is about $300. annually for a typical 2000 square foot house here in the Northeast. Period.

    Hopefully, that will answer his question. Unfortunately, all of the contractor responses do not answer his question because none of the responses addressed the comparison between a NEW mod-con and NEW conventional equipment. This is likely because the contractors have no data on this comparison.

    Whether the mod-con is a "waste of money" is a personal decision. I don't see how to recover the installation and maintenance costs in the life cycle of the machine, but that's just me.

    "Most people" have absolutely no understanding of the fundamentals of efficiency and how it is calculated.
    This post was edited by an admin on July 9, 2014 12:18 AM.
  • Gordy Gordy @ 5:57 AM
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    All assumptions

    When your doing it any which way the only proof is the installed equipment compared to the old that was there.

    The installer has the responsibility to steer the prospective customer in the right direction of equipment selection. Understanding the present installed system will give that installer a good idea of what the best choice will be for equipment, and what may be saved.

    In their past experience of what was achieved With marrying certain boilers with given emitters is where claimed savings can be made.

    So,as far as trying to decide whether a conventional boiler, or a mod/con fits is a little of what the consumer wants, and what the installer feels will be the best choice. Either way there will be savings usually.

    As far as savings of 50% in new conventional verses new mod/con I don't believe anyone would make such a claim. In the end all the consumer will know is what they are saving from existing to new what ever was existing.

    I still think that modulation and condensing still out weighs fixed output burners. This is where the afue fails for good comparison. It's just converting % of fuel converted to usable energy not how that energy is efficiently used.
  • bc3510 bc3510 @ 8:22 AM
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    You continue to cling to an erroneous definition of AFUE. Sorry, but it's not the combustion efficiency as you seem to want to believe.

    The combustion efficiency of conventional equipment is 80%.

    The AFUE in a typical installation is 70%.

    See the difference?

    Now, use the 70% and compare it to a 90% mod-con and see what you get.
    This post was edited by an admin on July 9, 2014 8:43 AM.
  • Rich Rich @ 8:06 AM
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    Math and Equipment

    are funny things . There is no choice with math , it is what it is . You can choose equipment and method of install .  BC , how bout this calculation for the sake of argument .  !00K mod con and 100K cast iron boiler . Price difference 500.00 . If I can make the mod con not short cycle , give it mass and modulate it , would there then be a CLEAR and CONCISE winner ?  You guys all chew on that for the day and I'll be back tonight .
    You didn't get what you didn't pay for and it will never be what you thought it would
  • bc3510 bc3510 @ 8:20 AM
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    80% versus mod-con

    If you can install a mod-con for a price differential of $500. as compared to the conventional equipment, the calculation would,have the mod-con virtually tied with the conventional equipment IF, the expected annual maintenance and repair costs would be less than $300. per year.

    Up here, nobody is going to service a mod-con for less than $300., so the maintenance costs are offset precisely by the fuel savings.

    If the mod-con needs any repairs in its lifetime that are greater than the conventional equipment, it's underwater from a cost standpoint.
    This post was edited by an admin on July 9, 2014 8:40 AM.
  • Gordy Gordy @ 6:21 AM
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    In the end

    The focus should be on which equipment will use the least amount of energy coming out of the meter. That makes the efficiency difference from high to mid a mute point, and maintenance costs.

    In Italy a mandatory yearly boiler inspection is 150 euro so they have that added in.

    There will and should come a day when there won't be a choice mid or high efficiency.
  • bc3510 bc3510 @ 8:27 AM
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    In the end

    the focus should be on what is the best value for the customer.

    Compare the initial installation costs, the fuel consumption, the maintenance costs, and the repair costs over the expected life of the equipment.

    Note that we have not discussed the expected life of the equipment. I have a suspicion that the 80% equipment will absolutely be more durable than the mod-con.

    At the end of the day, the numbers favor the conventional equipment.

    What you convince the customer to purchase is strictly up to you. I'm sure you don't present a fair and balanced argument between a new conventional system and a mod-con.

    If you take a look at a different industry, such as automobiles, your argument would require all members of society to purchase a Prius or a Mercedes turbodiesel because they offer the lowest possible fuel consumption. Such vehicles have the capability to save a consumer $1700. per year in fuel consumption compared to "conventional equipment".

    Note the $300 saving from your cherished mod-con pales in comparison to the fuel consumption benefits that can be obtained with a highly efficient vehicle.

    Why do I have a suspicion that you're not out there with signs and banners protesting the gross consumption from the average automobile? Why do I also have a suspicion that you do not own a Prius?

    Sorry, Gordy, the "lowest fuel burn" argument rings hollow in the grand scheme of things.
    This post was edited by an admin on July 9, 2014 8:33 AM.
  • Gordy Gordy @ 3:43 PM
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    Frame of mind

    So I see trying to make a system as efficient as possible when the opportunity presents itself means nothing to you. That's fine to each their own.

    As far as the auto industry your right but if the boat is sinking you have to patch the holes before you start to bail little ones count to, but your farther ahead to start with the big ones so talk to government on that.

    But if everyone has the what's in it for me attitude Dino juice will be gone for the future generations.
  • bc3510 bc3510 @ 3:56 PM
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    This post was edited by an admin on July 9, 2014 6:35 PM.
  • JStar JStar @ 6:10 PM
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  • bc3510 bc3510 @ 6:35 PM
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    It's valuable and worth keeping.
  • hot rod hot rod @ 6:54 PM
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    I do see the point that bc is making

    keep in mind a modern cast iron or copper tube boiler is much different from a 30 year old one, size and mass, ignition system, insulation, to name a few. A 100K cast iron is not that much larger than a mod con these days.

    What is the most expensive component to replace on a cast iron boiler? What the most common failure on a mod con? Price a inducer fan and motor, available only with the circuit board attached. A mother board $$?. These are the unknown, or known unknowns that can throw the numbers out of budget quickly.

    Not to go back too far, but standing pilot boilers ran troubleefree for decades, some without any maintenance over that life cycle.

    I know some contractors only install mid efficiency equipment in the very rural areas where parts availability is slim, and a service call round trip could ring up hundreds in fuel and windshield time, usually requiring two trips. Parts and multiple service calls could ring up a grand rather quickly.

    Keep in mind the elements out of our control, low gas pressure, ever changing fuel BTU content, obselete OEM parts, all realities. These are some of the common realities of 90% equipment. Ignore PVC venting for this discussion :)

    At the end it is what is best for the individual customer, and their expectations for on-going yearly maintenance.

    Many of us here embrace modcons, but we are able to service and repair our own stuff, the consumer doesn't always have that option.
  • bc3510 bc3510 @ 7:18 PM
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    I was seriously contemplating the GC124/3 with 74K input. It's got enough capacity for both domestic heat and hot water. Surprisingly it's almost identical in capacity to the water heater (GPVX-75L).

    They claim an AFUE of 85% but that's Buderas gaming the system. It does offer 83% combustion efficiency and my estimate remains that it will achieve a true 70% AFUE for the installed system.

    I believe you could install this boiler for 1/3 of the typical installation cost of a mod-con with all of it's associated auxiliary needs.

    If my water heater experiment proves to be unsatisfactory, this is the direction I will go.

    I'm a mechanical engineer and I don't consider maintaining a mod-con to be within my capabilities without factory training.
    This post was edited by an admin on July 9, 2014 9:48 PM.
  • hot rod hot rod @ 7:57 PM
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    I'm not a huge fan of a common water heater as a heat source. The small boiler would be my choice.

    We had this discussion many years ago at the RPA. Larry Drake the director always wondered why an "H" stamp is such a important feature. Why does a low temperature heat source need to be called a boiler even. Boilers is an old term dating back to steam days :)

    If the "heating appliance" can be built safely with all the appropriate LWC, over temperature, no flow, low pressure cut out, gas train safety, etc, why not. Most of these controls are standard on Euro origin mod cons, or the connection is provided for LWC switches for example. Most of the mod cons that came from off shore did not have the H stamp early on and proved to be equally as safe, or safer than H stamped products. The Euro boilers meet some fairly strict standards.

    Some of the tank style "boilers" on the market do not have the H stamp, and have adequate protection, like their mod con kin. Maybe it's an entire mod con assembly shoved into a tank? I think my tank style condensor has a vacuum cleaner motor for the inducer fan. Sure is robust.
  • bc3510 bc3510 @ 8:10 PM
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    small boiler

    I agree that I'd prefer a small boiler but for one issue.

    I cannot get the small boiler to provide sufficient hot water at low water temperature with an indirect. If I keep the small boiler at 150F (the max I would need), I cannot heat the indirect in any kind of realistic time if I want to maintain 140F in the indirect. There isn't sufficient delta T between the boiler water and the tank water.

    This now forces me to use a much larger indirect (with much larger heat exchanger) to transfer sufficient BTU's with a 10 degree delta T.

    The cost of this large indirect killed the entire plan for the small boiler.

    With the HWH, I maintain 140 (possibly 150 at the design day) degree water and heat the house with a variable speed circulator with outdoor reset. I can get 100 degrees to the radiators without the need for primary/secondary piping.

    I chose a 50 plate HX that can deliver 250K so that it will perform at at 10 degree delta T. This solves the "small HWH" problem.

    It does offer a lot of benefits.................
    This post was edited by an admin on July 9, 2014 8:13 PM.
  • Gordy Gordy @ 8:32 PM
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    Boiler temp

    Why would you not keep the boiler temp at 180 mix down for the emitters if 100 degrees is all you need BC? That would give a 40 delta for the indirect. I dont see the cost of maintaining a water heater tank temp at 140-150 all the time, and having to lose efficiency through an HX so its oversized to do the job.
  • bc3510 bc3510 @ 9:08 PM
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    180F boiler

    Sure, I could keep the boiler at 180 and pipe it p/s with reset and keep the temperature down at the emitters.

    But, then I've got a boiler losing a huge amount of heat because of it's 180 degree temperature.

    You cannot criticize a very well insulated hot water heater sitting at 140F when you accept a poorly insulated boiler sitting at 180F. Sure the amount of water in the boiler is considerably less, but I'd bet the losses between the two units are comparable due to the huge delta between the boiler water and the ambient temperature.

    I'm not convinced that the oversized HX loses any efficiency other than heat losses to the basement?? I suppose I could insulate it................
    This post was edited by an admin on July 9, 2014 9:11 PM.
  • hot rod hot rod @ 9:35 PM
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    DHW with a plate HX

    at my house and shop I generate DHW with 5X12 30 plate HX. The shop runs off a large solar tank, 180 gallons. I get a hot shower with the tank as low as 130°F via the plate. Size to a 10° approach on the HX. So at 130° on the "a" side I still see 120° on domestic side.

    A Harwill flow switch triggers an Alpha to run the "A" side. DHW up to about 2.5 gpm heats instantly. That Buderus could do that use a 3 way thermostatic to protect from cold return temperatures.

    In the winter my 120 Lochinvar Cadet produces DHW with an even smaller plate HX inside, but it does run up to 180°F.

    Summer months at the house DHW from a 30 plate HX on a 50 gallon Thermocon buffer. But it does get a solar pre-heat from another solar drainback system.
  • bc3510 bc3510 @ 9:58 PM
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    DHW with HX

    Mine is a 5x12 50 plate and I want to do exactly what you have...........a 10F delta between the supply side from the HWH and the side for the radiation. The water heater can go up to 155F (less differential) and I can then get the radiation side to 145F. Hopefully, I make it on the design day.
  • Rich Rich @ 9:37 PM
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    Did you mean GC124/3 BC ?  Just for accuracy .
    You didn't get what you didn't pay for and it will never be what you thought it would
  • bc3510 bc3510 @ 9:47 PM
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    Sorry, typo.
  • Gordy Gordy @ 8:24 PM
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    Hot Rod

    I dont think anyone here would disagree with that direct statement. It does cost money to be green on all fronts,except for my schwinn world sport 10 speed from high school I still have, and do ride for leisure;-) But sooner or later it should, and will be a requirement, and this will all be a mute point in cost of ownership no?
  • hot rod hot rod @ 9:26 PM
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    no doubt

    we will be forced to buy 90%. Old habits die hard, I'll miss those old cast iron "boat anchors" they served us well. Miss my 78 Ford 250 4X4 also.
  • Rich Rich @ 9:31 PM
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    Deleted Threads

    Can anyone name what they have in common ?  Whoever comes up with the correct answer first will receive a beautiful blue Langans Plumbing and Heating shirt . This hirt is made of 100% cotton and sports the motto " Considerate People , Considerate Service , Consider it Done " . Unlike some folks we spared no expense in this purchase for the comfort of our men .  I will determine the winner by the time stamps of the answers and contact the winner for their preferred method of delivery . Thanks for participating . Contest ends at 7:00 A.M July 10 2014
    You didn't get what you didn't pay for and it will never be what you thought it would
    This post was edited by an admin on July 9, 2014 9:34 PM.
  • bc3510 bc3510 @ 9:51 PM
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    Deleted threads

    All the deleted threads have Rich as a poster within them.

    Do I get my shirt now?

    BTW, at 8:06 am you posted an interesting question and stated that you would return tonight. I assumed it was to further discuss your $500. additional cost mod-con.

    Sadly, that didn't happen. You chose your usual denigrating path.
    This post was edited by an admin on July 9, 2014 10:07 PM.
  • Rich Rich @ 6:06 AM
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    Denigrating Path

    Not particularly BC , I simply decided to refrain from being sucked into the vortex of a debate about unrelated nonsense on a thread someone asked a specific question .
    As far as my return with an affordable solution I offer the following . I learned a long time ago that every job is different and requires a different approach and different equipment specific to that job . With the knowledge we now possess many of us know that depending on circumstances beyond our control both types of technology may gain benefit from mass due to zoning , changing heat load requirements , etc . There are also many of us whom regularly add components to systems that in our opinion are required and this is probably a good thing as we are professionals .  On many jobs that are retrofit where extensive work can not be done at that time because of many reasons but will or will not be in the future I sometimes turn to this product because it has built in air elimination , dirt separator , mass , modulating burner , condensing technology , superior materials and requires about the same maintenance as a cast iron boiler . When I do the math and include all the components and labor involved with them which I would include anyway this unit actually usually costs less to the consumer .

    Have a nice day and no you don't get the shirt . I will send you one though just for making me laugh . Send me your info in a PM so I can ship it .
    You didn't get what you didn't pay for and it will never be what you thought it would
    This post was edited by an admin on July 10, 2014 6:40 AM.
  • bc3510 bc3510 @ 9:18 AM
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    unrelated nonsense

    In reality the thread was a discussion that precisely addressed the question of the OP. He asked whether a mod-con would be cost effective when all of the costs for it, including purchase price, installation costs, fuel burn, maintenance, and repair costs are compared to conventional 80% equipment.

    I answered his question with the supporting math behind the answer.

    Others had the intense desire to dispute the answer, without any capability of supporting their opinion and the thread took off on a life of its own.

    When there was no more capability to argue the economics, the thread turned "green" and some tried to support the use of the mod-con for the fact that is offers lower fuel consumption despite its higher costs. This might be considered "unrelated nonsense" as it doesn't address the question of the OP.

    You've mentioned the Pioneer before and I agree that it's an attractive product. I do have some issues with it however:

    1) The smallest unit has only a 3:1 turndown ratio. It cannot get below 35K and this figure is simply too large for most of the houses that one would encounter on most of the season.

    2) Since it's not a hot water heater, you'd still need to keep it at close to 180F tank temperature to be able to use it with an indirect. Then, despite it's higher mass, you'd still need to pipe it p/s with another circulator and suitable controls to keep the radiation temps down. In this scenario, I do not see how to get the return water back to the boiler at a sufficiently low temperature to get anything close to 90% efficiency. Starting with 180 degree supply water kills the benefits. I see this a a problem with most mod-cons unless they have the computer controls that can raise and lower their temperatures depending on whether they are heating an indirect or providing heating for the radiation.

    There is an inherent problem with attempting to produce hot water at 140F via a heat exchanger and simultaneously desiring 100-140F water at the radiation. The size of the heat exchangers in the indirects are simply too small.

    If you must run the mod-con at high temperature to satisfy the HWH, you've lost much of the benefits of the condensing equipment.

    For all others who are in disagreement with the AFUE percentages and fuel savings obtained from them, I found a table that shows exactly the numbers that I previously stated. You can determine the precise fuel savings from every combination of AFUE that you might encounter:

    The table is in the literature near the bottom of the page.

    The fuel savings is most definitely based upon the AFUE ratios so all of that disagreement can now be ended.
    This post was edited by an admin on July 10, 2014 9:39 AM.
  • Gordy Gordy @ 9:43 PM
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    No shirt required.
    This post was edited by an admin on July 9, 2014 9:45 PM.
  • Harvey Ramer Harvey Ramer @ 10:08 PM
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    Water Heaters

    I have a long winded explanation of the phenomena that can occur when using a conventional gas water heater as a boiler. Problem is, I am quite to lazy too type it all right now;-)
    I will say this much. If you have a heat load that comes close, or matches the btu output of the burner accompanied by a system with some mass, that poor water heater doesn't have a snowball's chance in hell. It has to do with the way the heat exchanger is built and the location of the burner. Upon start up, the flue gasses are condensing at the top of the hx running down the tube to the bottom, evaporating again because the burner is directly underneath. More air is drawn in, introducing more water vapor. You get my drift. Burning water isn't cheap! I witnessed a water heater burning continuously for two weeks without getting the water temp above 75°F.

    Yes I installed it.
    Couple of reasons.
    I had to prove a cabbage head and all his relatives wrong. They knew it would work and I knew it wouldn't. They were so insistent and persistent that I figured well, I might as well get paid twice. And I did. 2 weeks after it was in I get a phone call. A whimpering voice at the other end of the line said that they are ready to listen and I should do what ever is best.
    So I did. Haven't heard a complaint since.

    The other reason was scientific curiosity. I got to watch the melee unfold before my eyes. I found it quite interesting to say the least.

  • bc3510 bc3510 @ 10:17 PM
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    too much load

    This system is piped effective p/s via a heat exchanger and the capability to kill the temperature in the tank quickly isn't present. Additionally, the HWH is protected from dropping below 120F via the circulator. It would stop completely at that point.

    A question:

    1) Is the HWH protected from the same situation that you described?

    You didn't mention any use of a HX and it might be assumed that the HWH was piped directly to the radiation.

    In my situation, the maximum load from the radiators will be about 45K and the HWH can produce a net 60K. Of course, on a cold start would be my greatest concern.

    We'll see if you get to laugh all over again............. :)

    I'll be the first to admit if it doesn't work.
    This post was edited by an admin on July 9, 2014 10:19 PM.
  • hot rod hot rod @ 10:09 AM
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    if the concern is being able to generate DHW on a design heating day, you could priortize the DHW. That is how the mod cons with onboard plate HX operate. Usually stopping a pump or diverting a 3 way zone valve is how they do it. Additionally some have an adjustable time out so the boiler cannot ignore the heat call.
  • bc3510 bc3510 @ 10:18 AM
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    No, I have that taken care of. The Tekmar 356 controls the speed of the HWH pump and offers complete shutdown of the pump if the supply temperature drops below the setpoint (might occur on heavy HWH demand).
  • SWEI SWEI @ 11:48 AM
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    Making a bang/bang boiler behave well

    is entirely do-able, as is heating a house with a tankless water heater.  My experience is that the added cost of doing so exceeds the cost differential of a mod/con boiler.  We still do a fair bit of this -- fixing bad installs, but I have yet to find a case where it pencils out on a new install unless there is solar or biomass or some other uncontrolled heat source in the system.
  • bc3510 bc3510 @ 11:54 AM
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    I'm curious as to how you get the mod-con to provide 180F water to a tankless and also provide 130F water to the radiation?

    Do most of those units have sufficient computer controls to know when they are sending water to the tank and when they are sending water to the radiaton?

    It seems like a daunting task.
  • Rich Rich @ 12:32 PM
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    Why yes

    they can and do recognize what is calling .  Most even power the circulator for the DHW as well as central heating circulator .  Sensor (10 -12k) usually sends signal to boiler , boiler adjusts SWT accordingly until demand is gone or programmed max time is reached than will return to space heating temp requirements based on ODR or some other programmed temp .  All this debate about mod/cons and you were not aware of these capabilities ? 
    You didn't get what you didn't pay for and it will never be what you thought it would
    This post was edited by an admin on July 10, 2014 12:33 PM.
  • bc3510 bc3510 @ 2:08 PM
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    I was not aware of these capabilities.
  • Rich Rich @ 12:40 PM
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    Performing 2 tasks

    sounds daunting ?  It's kinda like walking and chewing gum , gets even easier when you're not expected to do both at once .
    You didn't get what you didn't pay for and it will never be what you thought it would
  • RobG RobG @ 12:33 PM
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    Obviously you are shopping for price. What people are saying is that once you start adding all of the components together, you will end up with a Frankenstein of a system that costs more to assemble than a Navian CH-180 that is actually designed to do domestic and space heating, carries the H stamp, has built in controls for outdoor air reset and DHW priority and will take up less space, satisfy your homeowners insurance requirments and be easier to install. Oh and don't forget the AFUE is higher than your water heater. 
  • bc3510 bc3510 @ 2:09 PM
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    What I am "shopping" for is the lowest cost of ownership.

    The purchase price is simply one piece of that puzzle.

    Be assured that I will not have anything close to a "Frankenstein" of a system. This one is about as simple as it gets.

    We will see who wins this game in a year or so.
    This post was edited by an admin on July 10, 2014 2:13 PM.
  • Rich Rich @ 12:37 PM
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    Question for BC

    Is your home hot water heated or steam heated at present  ?
    You didn't get what you didn't pay for and it will never be what you thought it would
  • bc3510 bc3510 @ 2:11 PM
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    You already know I purchased the GPVX to provide both functions (domestic heat and hot water).
  • RobG RobG @ 3:56 PM
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    Once again BC, you are right. Nobody has ever thought about using a water heater as a heat source before. You should patent your idea! You will show us! You will have the last laugh! Dr. Frankenstein would be proud.

  • bc3510 bc3510 @ 4:24 PM
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    do you fellows persistently return to my water heater? I never bring it up for discussion and it isn't installed yet and I don't know if it will be successful or not.

    But it bothers you to no end?

    If it works, I'll let you know. if it doesn't work, I'll let you know that as well.

    I consider it a good experiment with low temperature supply water and the use of gas for fuel, and the cost is relatively low and the payback period is about 1.5 years..

    I hardly expect any professional to install such a system and would never attempt to convince any contractor to go down this path.
    This post was edited by an admin on July 10, 2014 4:31 PM.
  • Gordy Gordy @ 6:10 PM
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    It is less than professional, and people are going to lurk, and see that someone is doing it so that makes it okay especially if a professional condones it. Its one thing to experiment when you know what you are doing, and another when you do not know what your doing. I'm not insinuating you.

    Another in my opinion is you want to debate cost of ownership from conventional to mod/con without the full understanding of the technology. Disregarding everything that comes in the box of one verse the other. That's worth loads to the installer, and the consumer in the end. Your using a water heater a step below conventional even, and also purchasing loads of extra parts to make it do what you want when in fact the seemingly more expensive option comes with all the parts all ready assembled into a neat plug and play package. You get what you pay for. The water heater will never approach the efficiency of a conventional boiler. Now you could do what Rich does, and use the HTP product Pioneer which has the technology built into the over all purchase.
  • bc3510 bc3510 @ 6:30 PM
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    Fair enough

    I thought that some folks might find it interesting, but you make a valid point.

    I'll not say another word about it.

    Regarding the comparison between the conventional unit and the mod-con, my statements made certain assumptions regarding the installed cost of the mod-con. You might also recall that Joe noted the installed cost of the mod-con is about $2.5K more than the conventional equipment.

    I really don't need to know exactly what appears inside the box for the mod-con...........I only need the installed cost relative to the 80% equipment.

    If you want to debate that figure, maybe you should consider doing it with one of your colleagues and not with me.

    If it is worth ":loads" to the consumer, then I might suggest to you that he'll purchase the mod-con. However, even as you write how erroneous my analysis is, you fail to provide any data whatsoever to support your claim that the mod-con results in lower costs at the end of the day.

    I provided the data as I see it. None of you have refuted it and you wish to cling to this misguided notion that the mod-con results in lower overall costs for the consumer.

    Sorry to disappoint you, but the Pioneer has no more capability in terms of a "complete package" than my Smith. It only provides more efficiency because it's a mod-con. I still need the indirect tank with a heat exchanger built in, and I still need another circulator and I still need the controls to ensure that the HWH is satisfied before the radiant. And, worst of all, I cannot get the Pioneer to run at temperatures that would allow it to condense. It has no controls to enable two different water temperatures. It is most definitely not a plug and play package..............all it is is a mod-con.

    You've clearly got some mis-information regarding the Pioneer, and yet you choose to believe whatever Rich has to say about it, because he's a contractor.

    Finally, you make the statement "a water heater will never approach the efficiency of a conventional boiler".

    Again you speak without any facts. I've done the research and the GPVX has a combustion efficiency of 80%, just about the same as a conventional boiler. It's not your typical water heater. But, you wouldn't know that because you haven't done the research and your mind is closed.

    This post was edited by an admin on July 10, 2014 6:53 PM.
  • Rich Rich @ 7:21 PM
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    mentioned the Pioneer as a comparison to a conventional cast iron boiler in this thread and as a comparison of same the 55 gallons of mass allow the Pioneer to be held out for a longer period between cycles .  My comparison as far as the system you will install in your house was the Versa Flame which is an identical plug and play package developed by professional engineers to do exactly what you want in your home . Many guys still have the need to build a wall full of pumps and controls and valves and all sorts of shit that is unnecessary when they could order a package that has it all and is less complicated but they deem too expensive . What you are firgetting is the basic rule of business , time is money , at least mine is . You and others can build all the crazy trash you want at the end of the year I will spend hardly any time on service and will have completed 4 more complete projects than my peers . Please be accurate BC , I will engage in constructive discussion forever , anyone here can attest to that but I have no time for nonsensical garbage . By the way , what you are about to embark on was tried and failed long ago, this is the reason equipment like HTP has developed was developed . The difference between your GPVX and ANY boiler is this , the boiler was built to run 24/7 for 5-7 months a year , under those conditions your GPVX will end it's first season seeing as much use as it would just being a water heater for 6 years . Have fun getting warranty service from AO  
    You didn't get what you didn't pay for and it will never be what you thought it would
  • bc3510 bc3510 @ 7:49 PM
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    I know exactly why you mentioned it and it would be a fine substitute for a conventional boiler.

    What it will not do, and what your colleague is misinformed about, is to provide a complete package, ready to go, out of the box.

    It does need all the controls that a conventional boiler would require to function effectively. Unfortunately, all of the benefits of it's condensing capability will typically be lost in such an application.

    Yes, the Versa Flame is exactly the unit that would do the job. And, for a contractor, where time is money, it might be a perfect solution, but I find it hard to believe that it would be the lowest cost solution.

    You are another individual who wishes to speak without knowledge of the product or the system, despite your claim that you need all the data from others. For your information, the GPVX offers a net 60K with 75 gallons of mass, and the building requires 42K on the design day.

    You'd be woefully mistaken if you thing the GPVX cannot handle that loading for five years.

    BTW, I'll be sure to let Smith know that their side loops which they provide just for the purpose of space heating should be eliminated because Rich said the unit could never be used for space heating and, of course, he knows more about the GPVX than the engineers employed by the manufacturer.

    Talk about nonsensical garbage.......................
    This post was edited by an admin on July 10, 2014 8:48 PM.
  • RobG RobG @ 3:19 AM
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    Actually, your GPVX was designed to replace the woefully poor Apollo water heater design. They were used in cheap condos and small houses to operate with an air handler. I have replaced a ton of them. They are not made to last, they are made to satisfy the warranty period. Period! If you were to post the costs of all the parts and pieces of the scabbed together system, I can assure you that a Navian CH-180 will be less expensive or at least even. The biggest cost savings is in the labor needed for installation. I am just using the Navian as the least expensive combi that I know of as an example, for a few dollars more you can improve from there. Are you doing the installation yourself?

    As to the "critical error" you told me I had made in a previous post, the water heater WILL scale up quickly due to the fact that it will be running MUCH more WITHOUT make up water, the dip tube in a water heater flushes the bottom (a bit) as you use hot water. The scale will bake on the bottom of the tank, not to mention the flue gas condensation eroding it from within. I just find it hard to believe that a mechanical engineer would do this. (actually, now that I think about it, I'm not surprised)

    As well, you are not doing the same thing as Hot Rod is, you are doing the complete opposite. His boiler is a closed loop and his domestic goes through the flat plate. If he did it in the manor you are the heat exchanger would foul up quicker than you could whistle Dixie.

    This post was edited by an admin on July 11, 2014 5:27 AM.
  • bc3510 bc3510 @ 8:51 AM
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    How long to you really expect the Navien CH-180 to last? It has dual heat exchangers, that are running with makeup water very similar to the GPVX. Do you magically believe the Naviens heat exchangers are going to last more than the GPVX heat exchanger? Have you read the Navien's manual with all the cautionary statements about water hardness and warranty exclusions because of it? No, you've done none of that because of your love affair with the mod-con caused you to go blind..

    Are you forgetting about its expensive technology and internal controls? Do you really think it will be still functioning in 10 years? No, I'm quite sure you don't and that is in your best interests.

    Don't you think I already know the estimated life expectancy of the GPVX? It will last the warranty period, six years, and not more. Then I'll consider how it did overall and decide what to replace it with. It cost $800. BFD.

    And, let's be really have no idea on how much the drip tube cleans the heat exchanger with new makeup water..............banking on that happening in a big way probably isn't realistic. Sure the unit will accumulate more scale than it would normally have with just DHW use. The amount, however, cannot be predicted by you in advance. The factor of the water hardness was clearly overlooked in your conclusion, probably because you don't know what it is.............because you never asked.

    With regards to costs, have you forgotten that you probably are not going to run the Navien successfully in a high mass system without a buffer tank?

    And, speaking of costs, if you can procure the Navien and install it with its intake and venting piping with a buffer tank in parallel to my existing oil burner for $2,000. then please come right over and I'll put the cash right in your hand. Otherwise, all of your cost estimates are considered false.

    You also fail to recognize my desire to avoid the high degree of technology, maintenance, and repair that is common with the mod-cons. Just like my vehicles, I refuse to be at the mercy of another individual or company to provide what is necessary to get the unit running again. I do not have the desire to get factory training on the Navien, which is the only way that it could properly be maintained or repaired.

    Finally, what do you think the repair costs will be on the Navien for 10 years? I can already tell you what the repair costs will likely be on the GPVX. That figure for six years is likely to be ZERO. When you figure your repair costs for the Navien, let me know your labor rate to travel to the customer, troubleshoot the POS, order the part, and return for a second trip to replace it (because we all know that you won't stock those expensive parts).

    Unlike yourself, I don't find it hard to believe that a contractor is wedded to a specific technology because it makes him the most money and he is unable or unwilling to look outside the box at a lower cost alternative that is unlikely to cause the owner ANY repairs for its entire six year lifetime..
    This post was edited by an admin on July 11, 2014 8:57 AM.
  • RobG RobG @ 9:06 AM
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    Dude, you really need to chill out. I am just stating my opinion. You can do what you want to do but you cannot choose the consequences (someone on here uses something like that as there tag line). All that I am saying is that what you are trying to do has been done before, it even makes sense in some applications. I personally don't think that it fits your scenario. But opinions are like you know what. Do what you want.

  • bc3510 bc3510 @ 4:16 PM
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    All I ever wanted to do was to show you this system without any ongoing demeaning abuse of how and why you believe it won't work.

    None of you have actually attempted it with the exact hardware that I am using under the exact same conditions that I have. None of you asked about my DHW usage and the fact that I have a huge HWH with a demand of only 25 gallons per day. This, effectively, gives the GPVX all kinds of headroom for space heating.

    I bought it for a song and I simply want to try it and see what it does.

    I already told you all that it might fail. I already said that if it fails, you'll be the second to know.

    I thank you for your points about how the heat exchanger will fail early and you might be correct. I will keep a running account of the exhaust temperature and we can compare the deterioration of the heat exchanger over time.

    Instead of condemning this system outright because you believe it will be an abject failure, all I request is that you defer judgment.

    You all may get the last laugh. I can take it if and when that occurs.

    I did not jump into this project without some careful planning and with the knowledge that it's not the "preferred" way to go.

    Whatever it does, you can be reasonably sure that I will save 50% in fuel costs by switching from oil (with the identical system efficiency of the oil boiler). Whether I can make it to 60% will completely depend on the increased efficiency of the installed GPVX (if any).

    I spent $2800. in oil last year. Run the numbers.
  • Zman Zman @ 11:13 AM
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    Agree to disagree

    None of this is a personal attack. Different people have different opinions. Everyone is wired differently and not everyone will come to the same conclusion when presented with the same facts. That's life...
    It would be more productive to have a heated debate over what brand of truck you should drive.
  • bc3510 bc3510 @ 4:20 PM
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    With a truck, there can never be any winner to the debate.

    With the GPVX, either you all will be correct and the unit will suffer an early demise or will burn gas with reckless abandon, or I will be correct and I will save more than 50% on fuel and the GPVX will last for six years (my planned date for its demise).

    We will know the final answer if you can all just be patient and wait for the data (and, if, you all agree that I can post it. At the moment, I have agreed to drop it completely so as not to mislead people who are unsuited to attempt such a project). I'd like some agreement before I start a new thread on it. I think you all might find it interesting to see the actual efficiency of the GPVX and it's ongoing deterioration.
    This post was edited by an admin on July 11, 2014 4:30 PM.
  • hot rod hot rod @ 11:59 AM
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    good and relevant questions

    I believe the questions and points discusses are in fact on the minds of our customers, home and building owners.

    There are so many way to heat hydronically, it's good to have choices. If the products are approved and listed to heat water, and installed in a code like fashion, they should be considered.

    Pretty much every water heater manufacturer now has a boiler offering, and some have heat pump, solar and solid fueled offerings.

    Oddly, doesn't Canada still approved combined DHW/ radiant with water heaters? .
  • bc3510 bc3510 @ 4:28 PM
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    for an enlightening post.

  • hot rod hot rod @ 6:00 PM
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    there have been products, over the years

    built to do exactly what you have in mind. One of the finest was designed and built by Robert Bean up Canada way. He designed a line of beautiful and functionally acurate ZCP. Zone Control Panels. One version was built to add onto a water heater to add a small, or large, it the tank could provide it, radiant zone. inside a nice powder coated box was the FPHX, pump, electronics, mix valve, balance device, all the correct components. I put a few in, 12 years ago or more, I'll bet they are still running. Possibly the WH they were connected to :)

    I think Danfoss bought the company, Wirsbo sold them for a time, maybe Robert and some partners bought it back from Danfoss, been a while.

    He was on the right path, contractors balked at the cost and that it took some of their skill set out of the installations.

    I believe AO Smith offered a module for some time also.

    Bradford White tried to jam the HX inside with the CombiCor, great idea, bad choice for the coated aluminum HX. The ones that did last 10 years, considering the @ $900 cost, probably penciled out nicely for the customers. Bradford White did, by the way, stand behind every one that failed with replacements, or two separate WH option. Good for them.

    You are correct in the big "unknown" being yearly and ongoing maintenance and repairs for the higher tech. Keeping in mind some contractors are in excess of $200.00 / hr. for that service work.

    On the plus side the new mod cons seem to have many, most, of the early glitches worked out.

    Early inducer motors and fans the flew apart- gone. Ignitors that were un-dependable- gone. leaking HX and connections- gone. Parts availability and knowledgable tech support, mostly gone.

    In all these examples it's playing the odds. Will it break, when will it break, is it repairable, what are the repair costs, will the manufacturer be around in 10 years, on and on.

    High efficiency is here to stay, pick your partner, stay current on product, maintenance, design, upcoming technology, and do right by your customer.

    My 1978 Ford 250 was never in the shop in it's entire career. My last Ford "highly engineered" 6.0 diesel left me stranded 3 times before it had 20K, a couple weeks of lost revenue, sold at a loss with 60K. Go figure those odds :)
  • bc3510 bc3510 @ 10:18 PM
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    I agree

    You can't buy the old F250 anymore even though it was far more dependable than anything you can purchase today.

    I have a suspicion that the new mod-cons, although better than they were, still pack a lot of technology into a very small box.............and that box is going to need maintenance in a big way. If we use your figure of $200. per hour, the box is going to require a minimum of $400 per year. There goes any fuel savings...............

    Speaking of the mod-cons, SWEI posted a very interesting paper from the Brookhaven National Lab which compared the ci boiler with a mod-con. They did it under very well controlled test conditions and they provided the results on page 23.

    Even I was a bit surprised to find the system efficiency of the conventional boiler is within 9% of the system efficiency of the mod-con at all outputs above 7000 BTUH. The test conditions, however, heavily favored the ci boiler................fired with oil and distributing to fin tube radiation. Gas with radiant or with cast iron radiators would probably offer a much better result for the mod-con............closer to the 26% difference that I previously estimated.

    If this doesn't give folks a real pause before they consider a mod-con, I don't know what would.
    This post was edited by an admin on July 12, 2014 10:33 PM.
  • Rich Rich @ 11:42 PM
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    Bc .  There are so many things to consider when debating this subject .
    1 Is the boiler to be placed in a new home or retrofit ? Many of the homes I enter to replace a boiler have way too much baseboard , this allows me to determine by way of heat loss calc what the max temp required is and with ODR we can make  mod cons sing and have regularly experienced greater than 35% savings for space heating only , the number grows when we can install DHW also .
     Many of these same houses this is not possible and I can only speak for myself when I say I replace those like for like (but smaller most times)
      Then you will get the house that has undergone extensive envelope improvements and has an point 3 ACH NAT performance . You can't really introduce cold air into the space for combustion and increase the heat loss of the structure. You don't want to size the DOAS system for that , if there is one , many times that was not done in favor of exhaust only which would compound the combustion air problem .Now these poor homeowners have a real problem they are gonna die without the mod con .  I don't believe you appreciate the balancing act many of us are doing out here to DO THE RIGHT THING , save people money every month , make them comfortable and be able to sleep at night .
      The world we are working in is challenging . Competition is offering garbage and putting people at risk and in jeopardy . They install stuff that does not work , they don't do heat loss calcs , they don't know what head , Delta T , OAT , ECM , reverse return , P&S . It's terrible and the attorneys are just sitting in their office heated by mod cons waiting for the phone to ring . Hell , we even have utility companies administering incentive and rebate programs that make you use a mod con in a house where it does not belong and then slap a direct vent , PVC exhausted water heater right next to it because you cannot have an orphaned chimney without enough BTUs to heat it up . These jobs are where most of your horror stories come from . I see boilers all the time where the homeowners would like them ripped out and the only problem is the installer . I have mod cons out here that have run trouble free since 1995 and I have mod cond that the folks do not want service for whatever reason that become a problem .
      I also have replaced more cast iron boilers installed by some knucklehead that thought just run them at 130 for radiant and return em at 110 , they'll be fine .
     New houses are a completely different story . The guys that you have been exchanging with likely as I would rather be part of a design team during conception and build a house to suit what the occupant wants as opposed to designing a heating system to an architects attempt at an award for a giant turd he can publish and toot his own horn about to the world . This is the way it is starting to be done now .  Please take a look at the attachments , this is a house we are about to break ground on , I have given the details at 5* w/ 20 mph wind and 28* w/ 20 mph wind . Piping is designed to have minimal head loss , all panels will operate at 10* DT and the boilers will condense 100% of the time .  This house will consume no more than 2255 therms annually . NJNG budget amount for this house will run right about 210.00 per month . This is what most of us here do , maybe this will explain where we speak from .  A lot of time was spent this winter helping folks tell their contractors what they did wrong so they could fix it , Maybe you could help us in the future .
     By the way , I have seen what you are ready to embark on . Be very gingerly putting that in place . I have seen 3 units set up like yours where the glass separated or chipped and the manganese levels were terribly dangerous .
    You didn't get what you didn't pay for and it will never be what you thought it would
    This post was edited by an admin on July 12, 2014 11:47 PM.
  • bc3510 bc3510 @ 12:38 AM
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    Firstly, I'd like to thank you for your professional response. I appreciate to discuss the subject like a gentleman.

    I do appreciate the work that you do. I have seen some of your designs and they are highly detailed and carefully engineered. The capability to properly design a brand new system for new construction is surely very satisfying versus dealing with the people who had some POS installed and need it fixed because it won't perform anymore. BTW, they also don't want to spend more than $200. on the repair............ :)

    I have titled my response as "crapshoot" also.

    This is because the capability of the average homeowner to find a contractor such as yourself, who will actually do a Manual J load calculation on the house and also calculate the radiation room by room to properly determine if a mod-con can successfully be incorporated is just about ZERO. You probably know that the industry has far more "contractors" that will slap in the cheapest mod-con they can find without the slightest clue as to how to pipe it or vent it. Then, the result is an absolute train wreck for the homeowner, some of whom can ill afford to spend another $8K to replace it.

    The risks of getting a contractor of this type are very high.

    Therefore, I come from a conservative position. When facing a huge risk with an uncertain outcome, take the conservative approach. The chances of the average contractor successfully installing a conventional replacement boiler are good. The loss in efficiency between the conventional boiler and the mod-con are acceptable (26%). For most homeowners, this conservative approach is more suited for them, because they cannot ever determine, in advance, if the mod-con can be properly installed, operated, and maintained

    Is it possible to successfully install a mod-con and have it be durable for 10 years? Of course. But, very few homeowners can vet a contractor properly to ensure that will occur. I'm not even sure I could properly vet a contractor to verify that the specific mod-con that he wants to install will do the job that I need.

    The world has definitely evolved into hardware that is far more complex than most of the people in the industry can wrap their heads around.

    We balance jet engines for a living:

    This business has also grown far more complicated in recent years and the demands on our skills and our time dealing with people who don't have the background and who potentially end up with a disaster of a system by others is very high. We also must assist certain customers to fully replace tools provided by others who should never have originally offered such a tool.

    I understand and respect your misgivings about the GPVX. Only time will tell if the decision to utilize it was a mistake.

    Thanks for the note on the Manganese. I'll be extremely careful with it (it's in the basement as I speak). Is there a way I can test for that issue?
  • Rich Rich @ 8:26 AM
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    You'll know if it is an issue by the color / tint of the water leaving your faucets .  A simple test from a sample at the incoming water and one from the drain at the bottom of the heater will tell you if it is elevated .  I had a customer whose home had city water that was fine at incoming in every way but with readings if I remember correctly around 450 ppm after the tank . Manufacturer tried to state that water was too soft , it was in fact point 007 low . A nice letter from the attorney finally convinced them to warranty and replace the tank .    
    You didn't get what you didn't pay for and it will never be what you thought it would
  • Rich Rich @ 8:45 AM
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    Customer Attitude

    I always find myself walking away from jobs because I won't install what some idiot told them would work . Hell , I can sit on my couch with my hand in my pants watching television and not lose money and worry about being sued . That approach has zero overhead .  I have counseled too many attorneys at this point on what was done wrong and 100% provable to even entertain the thought of doing it wrong . I educate my potential customers and let them make their decision . I also offer to design the systems for them so bidding contractors can bid apples to apples while at the same time including my bid in the form of a budget for the system , many times they figure out they cannot really afford radiant or whatever it is they are seeking . Then you have the guy that watches DIY TV , you go to his house , measure , design , provide price and he tells you he saw on DIY where it can be done for 10.00 per sq ft . You point out to him that he is missing one very important point , you're not doing it yourself ,I am doing it for you . Fact is that almost all consumers will pay 500.00 for a 5.00 job but piss and moan about spending 5.00 on a 500.00 job . Imagine that  They will buy the newest I phone every 7 months but will skimp and be cheap on the equipment in their largest investment , their home .  
      Everything we use today damn near requires maintenance . Fact is with proper equipment selection , design and installation a whole lot of maintenance is not required .
      So I see now what you do . Let me ask you this . If some other engineer that was not in your exact field came and told you he had a better way than you and you had already seen people attempt that unsuccessfully or in a manner that the longevity sucked what would your response be ?  I am guessing you would be frustrated with that discussion . Well , at least you're experimenting in your own plane and not someone else's .  
    You didn't get what you didn't pay for and it will never be what you thought it would
    This post was edited by an admin on July 13, 2014 8:58 AM.
  • Zman Zman @ 11:41 PM
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    Why do you insist on turning every post into a defense of your purchase of a boiler or water heater or whatever it is?

    The Brookfield study accurately represents the efficiency difference between mod/ cons and CI boilers using baseboard heat, not he best application for mod cons.

    I think it is great that you are happy with your purchase.i personally would not use it for that application. Others on this forum agree.

    Can you please let it rest?

    Come back in 20 years and tell everyone how reliable it has been and how wrong we were.

    This post had nothing to do with you or your water heater, nor does your banter add anything to the discussion.

  • bc3510 bc3510 @ 11:45 PM
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    say what?

    Can you point to anything in my response to Hot Rod that has any mention of the water heater?

    If you bothered to read the thread, I never made a single comment regarding the water heater until Rob G brought it up............yet again.

    Maybe you ought to chastise him?
    This post was edited by an admin on July 13, 2014 12:00 AM.
  • Zman Zman @ 12:29 AM
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    You seem to recognize the futility of the truck argument. Yet you hold onto this one.
    How about getting together for a few hours of TIC TAC TOE?

    I am just pointing out that you have a habit of hijacking threads in order to validate your selection of heating systems.

    Start your own thread and start your own argument (again) I will gladly ignore it
  • bc3510 bc3510 @ 12:42 AM
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    Reading comprehension problem?

    I never hijacked anything on this thread. I responded to the OP............that's it.

    Some of your cohorts decided to ridicule me and bring up the hot water heater again. I responded to it.

    Again, if you have a problem with the fact that THEY brought up the hot water heater, take it up with THEM!!

    Maybe you should have ignored this thread as you certainly didn't read it.
    This post was edited by an admin on July 13, 2014 12:47 AM.
  • Gordy Gordy @ 12:33 AM
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    Oakley White paper

    What to take from it was its intent.

    1.Oversized emitters a plus.
    2. Mod/cons condense with high temp emitters IF number one applies.
    3.Mod/cons are more efficient than conventional equipment.

    What you chose to take from it is your intent. For you that is cost of ownership vs efficiency.
  • SWEI SWEI @ 2:52 AM
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    The PDFs were posted

    in response to a post referencing a dwelling with existing high temp baseboard.  The intent was to show that even an inferior emitter system (high temp baseboard) can benefit from a mod/con boiler.

    The initial introduction of modulating condensing boilers into the American market was a bit bumpy.  Most of us who have been at this long enough have seen our share of bad installs.  The products and the installers have both come a long way in the past two decades.  I have no qualms about selling and warrantying them, nor should any competent and conscientious tradesman or contractor.
  • hot rod hot rod @ 11:33 AM
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    good, and healthy

    to discuss and understand differences in opinions and opposing views. Our elected leaders should embrace that concept, again.

    Numbers are what we have to base pretty much everything on, temperature, money, projections, guesstimates, etc. Sure they can be tweaked to one advantage, the banking industry is good at that.

    In this discussion, time is the largest unknown. How much, for how long. Even with the best number crunching and accelerated testing, sometimes it's just a guess based on the data available.

    Also forces beyond our control, dirty power, changing fuel content, intake air building mouse turds, etc.

    Hats off to Pete for making that study possible and being one of the early condensing proponents.

    Keep in mind the MZ is no longer available, parts pretty much gone. So customers that installed them with that 15 year- 20 year formula, may not make out so well.
  • Rich Rich @ 12:25 PM
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    Monitor MZ

    Funny you should mention the MZ Bob .  We are doing a job now for a woman whose husband is employed by the gas utility . He , in his infinite wisdom retrofitted his former home with radiant , some embedded some sandwich . Non barrier tubing , electric stripped out water heater for a buffer laying horizontal , 20+ circs (B&G NRF22s) , no water treatment for heating system with well water system .  Female homeowner has house after divorce , pays monthly maintenance / repair contract , heat goes out in January , tech cannot figure out what is wrong , bypasses safeties & flue safety after being instructed to do so by office , states this is against his better judgement on written paperwork . House almost burns down , everything in house freezes , house destroyed essentially . Insurance company is ecstatic , they have the best case one could hope for , written negligence by an employee .  We spent 5 complete days flushing lines to my satisfaction ( Caleffi flush/fill) . Found so many problems with house other than what is obvious .  After dissecting Monitor I found the trap completely filled with lime scale .  Just an example of the so many things that can go wrong .
      Anyone who thinks your gas supplier is an authority on anything , think again . 
    You didn't get what you didn't pay for and it will never be what you thought it would
  • Gordy Gordy @ 12:32 PM
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    Original post, and drifting from a direct answer.

    I usually do embrace drifting off topic in a debate. If the poster is patient, and reads the posts something can be taken away from the discussion....usually.

    In this particular case it should bring to light there is no simple direct answer to his question. It's a case by case, wants, needs, goals, budgets for both installer, and end user.

    It's like debating which mod/con, or conventional boiler is better. Usually in the end it's about what is available in the area, parts, knowing the product line, features offered, and features really needed.

    Savings from a new install is always subjective especially if calculated by end user. So long as the customer is happy with those numbers is what really counts.

    In the end choosing not to offer a product line limits his business opportunities.
  • Rich Rich @ 2:28 PM
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    Most Folks

    have no clue about all the thought we dedicate to every single job Gordy . I think they miss the point that those hours which they never see are money well spent .
    You didn't get what you didn't pay for and it will never be what you thought it would
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