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    Combi Boiler/Water Heater choices (28 Posts)

  • AA AA @ 5:08 PM
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    Combi Boiler/Water Heater choices

    Hi All,
    I've been doing quite a bit of research on these boards and am very thankful for the information that it has give me. I'm a laymen, though not entirely. I think I'm knowledgeable but in reality I'm a first time home buyer so i only know that i don't know anything.

    Here's my predicament. the home we bought is a 2800 sqft 3  full bathroom, two heating zone house with brand new high efficiency appliances (re: water use). I have a wife, a 2.5 y/o boy and a girl on the way, so that will give you an idea of present and future load.

    Are utility room is a small space that was made smaller when a shower was put in in the adjoining bathroom, so all the plumbing, water heater (over 15 y/o) and boiler (32 y/o) are shoved into a corner with the pipes all out of whack and the boiler darting out into the door almost. I want to make space there for being able to move around and actually have room to do laundry... so combination unit is pretty much my only way into saving space and redoing that room.

    I have three quotes on the floor... and while i know we don't talk prices here, they range from under 10k for a Navien CH-240ASME, a Prestige Trimax Excellence for a few over 10k, and a Rinnai Q175 CN for over 15k.

    My biggest issue is not having enough water around, money isn't really the issue but a factor of course, space saving is an issue but all the combi choices save space... In terms of water, the GPM for Navien is 4.5 at 77 degree rise, TT is only about 3 at 70 degree, Rinnai is 4.1 at 75 degrees.

    I know from this board that Navien isn't a favorite at all, the TT seems to offer not enough GPM for my family though it's favored here, and the Rinnai is just hugely expensive. All quotes are from very reputable and experienced installers whom have experience with these particular models.

    I just dont know what to do, but i want to do it right and do it once... i don't want to wind up in the winter with not enough hot water and cold baseboards... I've considered a standby as an addition to this, but i may not have room. So one unit would really be ideal.

    Any help would be greatly greatly appreciated. I live in NJ.
  • Rich Rich @ 5:15 PM
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    in Jersey are you AA?
    You didn't get what you didn't pay for and it will never be what you thought it would
  • HomeOwner1 HomeOwner1 @ 5:27 PM
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    Also in Jersey

    Your quote for the Navien sounds really high. Our quotes were around the price of a standard 82% boiler price, which was about half of the quotes your are getting. We totaled up just the parts costs and the unit usually retails for a couple grand and about half of that for the rest of the parts for supplies. Then even more valuable, is the labor for the guy that knows how to put it together correctly!

    We have the Navien 240, and inquired with a few others before buying. So far so good and works just fine for 3 baths and a much bigger house then yours.

    We ruled out the Triangle Tube as well due to it not meeting our hot water requirements. Plus it was twice the price.

    Make your own decision and ask to speak to other people that own one. We got unbiased feedback from actual customers who owned one for a year or two before we bought one.
  • Rich Rich @ 5:34 PM
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    Could you possibly post a picture of your unit and piping ?
    You didn't get what you didn't pay for and it will never be what you thought it would
  • AA AA @ 5:57 PM
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    I'm in Union County

    New Providenc.

    i saw you on here Homeowner, and i know you've had a good experience... but i'm just not seeing any more of you to be honest, the rarity of your experience scares me a bit from navien...
  • JohnHenry JohnHenry @ 12:08 AM
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    My experience with a Navien CH unit has been good as well. No complaints through two full heating seasons.
    The bitterness of poor quality remains long after the sweetness of low price is forgotten.
  • AA AA @ 6:00 PM
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    I think because all of the piping will have to be redone, this space needs to be cut out and replaced, at least that's what i've been told by all of those who brought me a quote.

    The house is from 1962 and a lot of this was probably done a decade or so after that last... and it shows. it's just messy, and not preferable. Since we are looking to combine it does need to be tightened up. That said, i did think the quotes were really really high, but again. the companies i'm sourcing were all highly rated on Angie's List and other sites and i'm sure that's the premium cost also.
  • Rich Rich @ 6:08 PM
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    Angie's list

    scares me . Have already repaired couple year old jobs done by A.L referrals and the people I did the repairs for also recommended .  Lots of jobs can get done in the time A's List can turn bad . Nice guy , showed up , finished job , have hot water . 12 months later , that guy sucks , he's a thief , my stuffs broken .
    I am in Toms River . How crowded in is the space ?  Any of the installations you mentioned will have quite a bit of piping immediately around the unit . This stuff will take up some room also .  How much space is there in actuality ?
    Does 4.8 GPM at 77* rise interest you ?  Not a wall hung unit mind you but much less space required than what you have and is far superior to all the installs mentioned .  Send me your private E Mail
    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 August 20, 2013 6:10 PM.
  • AA AA @ 6:22 PM
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    There is room

    There is room once you redo the piping to put it on either wall around there, because so much space is taken up by the hot water heater and boiler now...

    4.8 at 77 degrees is better but it has to save space...

    I guess what i really want to know is people's experiences with the three makers. Whether i should just bite the bullet and also go the indirect route to ensure comfort? and so on, my options are many i think, and i am weary of making the wrong choice.

  • HomeOwner1 HomeOwner1 @ 9:19 AM
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    Hot water

    The thing will meet your water needs.

    One of the guys on here had some good advice for us.

    Measure with a bucket the gallons per minute. Figure about 60 to 80% of that number based on how you mix the hot and cold on your knob. For the Navien, we set our unit to the well water setting and put the hot water at 130 degrees. Seems to be the optimum setting for us.

    For us, it translates to about 3 showers going at the same time in the coldest day of winter. Otherwise you get about double or triple the flow in other seasons. It has never impacted us and notice no difference between an on-demand hot water systems and the traditional ones.

    We have never run out of hot water yet on ours with 3 bathrooms and a full house. We were also concerned about losing hot water. With these , you just lose pressure when you have every hot water faucet on at the same time in the house at once. On the old water heaters, you lost hot water when the tank emptied but kept pressure from what was explained to us. The guys on this forum can explain it in much more technical terms than me though.
  • AA AA @ 6:30 PM
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    I forgot to add

    The biggest cost here is the exhaust of the unit. have to go through the chimney since i have a lot of windows and no legal way to really mount it with direct out on the exterior wall, so it's on the inside wall is where the location will be. that means expensive materials for chimney lining and pipes etc.

    Rinnai is a really great compan form what i gather, but i dont see it featured on these boards as much, there is a lot of talk of anti Navien and pro TT but very limited Rinnai back an forth... and for the money the unit alone costs i hoped to have seen more about it here or otherwise.
  • HomeOwner1 HomeOwner1 @ 9:10 AM
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    Exhaust is just PVC

    In our case, it is a condensing boiler so it as just PVC up the old chimney to a new cap. Took them all of about 45 minutes to run the new exhaust. It was the easiest and cheapest part of the install on ours.

    We had the same window issue. We also prefer it that way, those things can put out a cloud of smoke and condensate. It is much better going up.

    The re-piping looks like it can get tedious.

    Ask to speak to people that own one.

    We happen to live in the same town as their east coast service center, so we figured if they would better support people in their own town. Or we could just drive over and give them heck if we ever needed to.

    As of right now, we are trending towards a less then two year payback on fuel savings. Our enormous previous oil boiler was a stark contrast to this thing. Not sure if you have such extreme circumstances. We would have seen similar fuel savings though on all of the condensing boilers, just this one was much less expensive and payback much quicker.
  • AA AA @ 9:43 AM
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    for the rinnai

    from what i understand it needs to be higher grade one. i also have a split level with tall ceilings on top floor and a stand up attic. maybe that's why. i have to think that it's the combination of venting/air intake and the repiping that'll be needed... otherwise i have to think i'm being taken for a ride with these quotes...
  • HomeOwner1 HomeOwner1 @ 9:51 AM
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    The highest quote we got was 7 for the Navien.
  • JStar JStar @ 8:15 PM
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    There is always a way!

    I'd prefer the Triangle Tube over the others. The installation will determine how much space is needed. All depends on what is required to make the system work properly. We run vent pipes through the chimney quite often. It should not add a major cst to the total job.
  • AA AA @ 9:44 AM
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    3 gpm isn't

    going to cut it though... especially at 70 degree rise, it seems dangerous to go that route and then have to get an indirect tank or something else to supplement that... no?
  • HomeOwner1 HomeOwner1 @ 9:50 AM
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    Need to measure

    It works fine for us.

    I am sure there are many other examples of homes like yours having on-demand hot water heaters. They work.

    Measure it to be sure then.

    Where did the 3GPM come from?

    Our shower heads are around 1.8 and we factored in about 60 to 80% of that flow being mixed in hot water. Tubs put out more.

    Good luck!
  • AA AA @ 9:53 AM
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    3 gpm is

    The TT, the navien is 4.5.

    Will ping you to chat over email, have a question.
  • Rich Rich @ 8:24 PM
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    How Many

    windows could you have ?  The Rinnai only requires 1 foot of clearance from windows horizontally or below .  Is the problem no way to get to the outside wall .
      If you only had something the size of a water heater , would that be offensive ?
    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 August 20, 2013 8:26 PM.
  • AA AA @ 9:46 AM
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    it's not so much how many

    But they are close to each other no clearance to exhaust with enough space by code, that's the feedback from all that saw the situation.

    by current gas fired burner is like a 27 inch box it's huge so is the water heater, both too old for their own good.  nothing would be more offensive than that...
  • Zman Zman @ 9:30 PM
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    The triangle tube is a condensing boiler with an internal 14 gallon tank. The others are instantaneous combi units. You don't need as many btu's if you have storage. You can also match your heat load more closely with the triangle tube. This will extend the life of the boiler and improve efficiency.What is your existing hot water heater? How does it perform?
  • AA AA @ 9:47 AM
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    but when the 14 gallons deptele

    no shower is going to accomodate that, smaller tasks sure, but the 3 gpm after that will be too low no? i mean they rate it at like 210gph on the first hour but then what?
  • Chris Chris @ 9:33 PM
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    How About This

    Should be avail next month. US version has a 26 gallon 316-Ti Stainless Tank and the warranty is lifetime on both the tank and boiler HX. No need to pri/sec piping either as long as the heating system flow rates need is less then 6.2gpm. Another nice feature is the installer can decided in the field if he wants to pipe from the LH or RH side. There is also a top piping option as well.
    "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 August 20, 2013 9:34 PM.
  • Zman Zman @ 10:55 PM
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    That Viessmann looks nice.
    The 19KW has a very useful heating range and with that much storage it can handle the demand spikes with no problem. That might be worth the wait.
  • nicholas bonham-carter nicholas bonham-carter @ 6:51 AM
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    Limited space for boiler

    Is there nowhere else in the house to put the new boiler/indirect? Perhaps the garage could have some space.--NBC
  • AA AA @ 9:49 AM
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    all the piping

    for basboards (which in split levels go INTO the slab) and the upstairs zones are all in one place, i can't imagine dragging all those pipes through the adjoining office into the garage, and doesn't seem like that would be any better or less costly of a solution.
  • hot rod hot rod @ 5:40 PM
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    maybe 3 gpm

    is plenty for your needs? Not many faucets or shower valves need more then 3 gpm to give you a good wash or shower. The limitation is when you try to run multiple loads. It's all about your lifestyle and how and when you consume DHW.

    Fast fill tubs are about the only load I have found that can outrun 3 gpm.

    It's very rare to fine a tank type water heater in a residence in Europe. The tankless movement has roots there and most folks I know with tankless style heaters, myself included, learn to live within their boundries.

    With my Lochinvar Cadet I have no problem taking a shower while either the dishwasher or wash machine are running. i suspect with low flow shower heads two could shower at the same time, remember you don't need 120F to shower, probably closer to 100F.

    Hard water conditions will require you to maintain the HX or tankless type heaters, but those same deposits lurk inside a tank type heater and drive efficiencies down.

    The answer is yours to decide, the fact that there are dozens of tankless brands of heaters, and combis, on the market, dating back to the 1980 Palomas, indicates the public is embracing them.
  • Zman Zman @ 11:58 PM
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    Not Tankless

    The triangle tube excellence and viesmann that Chris suggested are not tankless units.
    Trying to compare them to tankless is like saying a 40 gallon gas water heater only produces .85  gpm or a 80 gallon electric only produces .5 gpm. You cannot make the comparison without looking at the tank size. That' true, by the way.
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