Joined on December 29, 2008
Last Post on August 23, 2014
@ May 8, 2014 9:23 AM in Heat Loss discrepancyMethodology..What's in the wall? What type of windows, etc all go to infiltration. There is no way that this particular house needs 46 btu/hr sqft based on that 140K heat loss.
I just did a 9,000 sqft house, all radiant, total heat loss = 54K. Average conventional heat loss for a 3,000 sqft house R-19 Walls, R30- Attic, Low-E Windows is around 40K. I think Rich's number for his last project is much closer to what the heat loss of this house is then the original poster.
@ May 8, 2014 7:53 AM in Heat Loss discrepancyADS since its conception 20 years ago. It is a Manual J based program. The critical part to the software for accuracy is air exchanges.. If a home has R-19 Walls, 30 Attic, Updated windows I use a .75 for air changes when doing baseboard. R-11 Walls, i'll use a 1..
I would question that 145K was high IMO. That's 46 btu/hr sqft based on the square footage you posted. At that rate curtains would be blowing from all the convection pouring from the board..
@ May 3, 2014 7:38 AM in List of small mod/consInstallers and homeowners tend to pay too much focus to the heating plant and the boiler room. They also don't develop what I call long term heating system upgrade plans.
There's a lot of throwing about percentage numbers about savings in retrofit systems and many lose site of opportunity. I never for the most part see us talking about water temperature. HeatPro always brings in the small cast iron boiler and many others about the low end of the modulation rate. As SWEI pointed out that is generally the culprit and cause of short cycling, not the high end. Boiler will never get out to the high end if the system doesn't ask for it.
The opportunity I'm talking about is this. How many of you have walked into a home with simple residential baseboard where the homeowner wants a Mod/Con and all you give them is the Mod/Con? The boiler is just a heating plant, it makes energy and that for the most part is its job period. There's an entire system out their that needs the same upgrade as you just did in the boiler room.
Sit back and think about your last 5 installs. Was there an opportunity in any of them to develop a long term heating system upgrade. At the time you quoted the job, did you give the customer options to changing out that residential baseboard for high capacity board to get that water temperature down? No, Why not? Maybe you thought they couldn't afford it or maybe you did offer and they couldn't. Why not give the consumer the number to change it out, tell them to put away their pennies for next year and change out Zone 1. Maybe the following year Zone 2 and so on. Provide the customer with continually upgrades that will show in their utility bills year after year. Maybe even throw in that yearly service for free at the time you do these upgrades giving the customer even more value.
There are plenty of opportunities and tools available to continually upgrade a heating system. It doesn't mean just the boiler and this is an opportunity that in my opinion is missed daily.
@ April 29, 2014 9:36 AM in 2x8 Floor Joists 1/2 Pex with Heat Transfer Plates - Faced or Unfaced FiberglassIf you're using the extruded alum plates such as Uponor/Wirsbo Joist Trak no air gap is required. Heat transfer is direct from plate to floor. The benefit, quicker floor response time, lower water temp and even floor surface temps. Min insulation required is R11 but insulation is our friend so the more the merrier..Could care less about type its all about
If you're using those cheap tin plates, yup need the 2" air gap. But you'll give up the benefits of the extruded plates.
@ April 29, 2014 9:31 AM in Favorite Mod Con.Out in the market has been around for years. I'll take a Viessmann Vitodens 200 hands down over anything else on the market.
@ April 23, 2014 6:03 PM in What's your opinion on this design...Don't think its in the budget...lol..
@ April 23, 2014 5:51 PM in What's your opinion on this design...Way before I'd do that RMB and then use the extra $$ I saved to use Bumble Pumps..
@ April 20, 2014 9:10 AM in Boiler Protection PipingSimply use a 4-way vs a 3-way Mixing valve - simplifies piping and you get the same result.
@ April 1, 2014 11:42 AM in Navien 100,000 btu heatingNo. I have Ziggy's software and I use Uponor's ADS software.
You do see that they system side is only running on a 10 degree delta right? I used 160 return to simulate what installers think. That they are running a system side 20 degree delta supplying 180 degree water... It's just not the case. If you change that system return you system supply temp is going to decrease..
@ April 1, 2014 9:47 AM in How To Make Current System More Efficientreset the system not the equipment.. Use a 3-way modulating mixing valve. Does the pellet boiler have a 0-10VDC input in the control? If so, you can use a Tekmar control for the ODR of the boiler..
@ April 1, 2014 9:41 AM in Automag zone valve with intermittent run-away heatGary call Paul Ross up at Hydronic Alternatives, they rep Auto Mag 413-543-8733
@ April 1, 2014 7:33 AM in Navien 100,000 btu heatingBoiler/Primary Flow Rate = 5gpm
System Flow Rate = 10gpm
See attached....It's not btu/hr you need to worry about it's the (T2) System Supply Temp. Yes you can get 100,000 btu/hr but not of 180 degree water its impossible unless you're boiler is making around 190...
The PDF is converted from an excel file that I made into a calculator. I use it all the time on retrofit jobs to make sure my design supply water temp is enough to get the load of out the emitters.
I've had this conversation with Navien plenty of times. Once you bring it up they look at you like a deer in the headlights..
@ March 23, 2014 5:45 PM in Want to move from oil to gas boiler. Best way forward?Yes they publish a 120,000 btu/hr output. But what they don't tell you is at what water temperature. The on board circulator can only move 5gpm across the heat exchanger so if your heat loss is let's say 100,000 btu/hr and you need 10gpm across your system do you know where the other 5gpm comes from and its effect on the heating systems water supply temp? Snowmelt who claims is a Navien installer can't answer it so I wouldn't expect a homeowner to know it but I know SWEI does..
@ March 22, 2014 6:52 PM in Floor Sensing ThermostatYou can. Do it all the time. You can get them where they are programmable, sense floor temp, air temp or a combination of both. Very common when you have radiant with Hydro Air as backup or the consumer is looking for just floor warming..
@ March 21, 2014 11:04 AM in Burnham ESC vs. Combi Wall HungBut may I add one thing....What's in those 2 full baths? Human car washes or just regular shower heads? I also never understood why one would add another energy user when one piece of equipment could do the job.
Could the Navien provided 120,000 btu/hr for heating? Yup sure can but at what what water temp? The on board circ can only move 5gpm across the HX. so that heat loss Iron was talking about is critical and so is measuring and calculating emitter capability..
@ March 20, 2014 9:03 AM in Emergency contact info for Viessmann?Anytime that wiring harness see's wet you have to replace it. I had a few but never came across no fault codes, usually get a burner blocked fault. The only time I come across no fault codes is when you don't make the flow switch and its usually because the boiler itself is air bound..If you ever have an issue down the road and can't get a hold of someone be more then happy to help you out..
@ March 20, 2014 7:40 AM in Emergency contact info for Viessmann?Would have had you call me.. What was the issue in the end?
@ March 19, 2014 12:26 PM in Want to move from oil to gas boiler. Best way forward?The btu/hr output ratings are for DHW not heating period! The on board boiler pump will move 5gpm across the HX that's it period...Now how many btu/hr can you get out of that unit Snowmelt? After that the question is at what supply temperature..
And as a FYI they are not a different animal and cannot change physics..
To the original poster I'd take Tim's and Kurt's advice. They both are correct.
@ March 17, 2014 1:36 PM in Mod/Con Heat Exchanger DesignsControls are all smoke and mirrors to this point and that includes the new zone control being used with the K2.
From a total platform and I'm a Viessmann guy I'd look at Lochinvar for one reason and one reason only...I can control my boiler/primary pumps flow rate to match the boilers modulation rate.
Honestly, I could care less about the HX's at this point. If you're installing correctly and servicing correctly they will all last. This debate over HX's is like the debate of which Pex Tubing is better...They will all last if you do the right thing
@ March 17, 2014 1:25 PM in NG Combi Boiler versus indirect tank and boiler setupUtility rebates are for the consumer not the trade contractor. The Rinnai is a domestic on demand water heater the Viessmann is a boiler. So you have two different products not the same type of product.
@ March 14, 2014 9:57 AM in boilerYour question is very broad. I'll take the path of do the heat loss, measure emitters and calculate water temp needed to provide btu/hr to overcome the heat loss on your design day. Make the decision from there. Most homes are 35% over radiated so in many cases yes it does make sense to go mod/con.
Every job is its own and should be treated as such.
4 x (90 x 500) = 180,000 btu/hr
How is this 2100 sqft of snowmelt working properly and effectively? Snowmelt in order for you at 4gpm to deliver 300,000 btu/hr you'd be running a 150 degree system delta-t.