Need more heat - options?

JHR

Our boiler is in need of repairs and I had some time so I decided to take matters into my own hands and research what might be causing our long cold winters.  With the help of this board (and others) it's seems very simple.  Our house did not have enough baseboard radiators installed when it was built.  I've done a heat loss calc and I come up with 41300 BTU's for the 1st floor, we only have 40 ft of standard baseboard on the 1st floor.  2nd floor load came in at 34,600 BTU's and has 54 ft BB + 5400 BTU runtal panel rad.  So the 2nd floor is adequate but the 1st seems dismal.  I used -7F as the design temp and a 77F deltaT in case you're wondering.  And yes it gets that cold here. 



In Jan/Feb when it gets really cold out the house just losses heat and gets colder and colder, circulator runs constantly with boiler firing every once in a while but is not firing constantly.  Zone return water is usually so hot you can barely touch the return pipe.  House can usually maintain 60F using the boiler alone.  We had a Jotul direct vent gas fireplace installed a few years ago which keeps that portion of the house warm.  DHW is a 40 gal super stor that seems to be working great.  Current boiler is a 20 year old Peerless PDE-130 propane, which should have plenty of oomph for the house, and yet we freeze.  house is approx 2800 sq. ft above grade, 20 years old, 2x6 wall, energy audit done 3 years ago with no obvious easy fixes. All that seems to support the fact that we insufficient radiation on the 1st floor.



We've had a few Plumbing and Heating contractors in over the years and none has done a heat loss calc or looked at the amount of radiation.  I've had a couple of new folks in to do estimates on improving the situation but haven't gotten the exact estimates or proposals yet.  I have some questions for you folks if you'd be so kind:



Both contractors were talking up a Weil Mclain GV90+.  I was surprised they did not talk up a high eff. mod/con.  The 2nd contractor did talk alot about triangle tube but for some reason thought it was not a good fit (no heat loss done yet by him, just rule of thumb based on looking at house, sq. ft., etc.  He did ballpark 70K which is pretty close).  Is a WM GV90+ truly tried and true?

Both contractors said "you need more radiators".  1st just wanted to add which I don't think will get us where we need to be based on available wall space.  2nd suggested adding and replacing current BB with high output BB (don't know what brand).  Panel rads are going to be out of the budget based on how many would be needed, although that would be my preference.  Who makes a good high output baseboard?  I want to check the specs myself to do some calculations.

If I pressed a HE mod/con are we likely to be able to get the return water temp down low enough for it to be in it's high efficiency range? 

One more contractor coming next week any suggestions on questions for him?

Any of you folks work in northern VT?  No names showed up when I did a contractor search. 



Time is of the essence now, current boiler is having issues and I'd like to just get it replaced rather than put more money in it....although it tested at 85% efficient if I believe the energy audit, not sure how they tested it.  So if I got it fixed and it lasted 10 more years I could just put the money from the new boiler into a panel rad retrofit. Any thoughts on that?

Rich_49

Smiths Environmental

Is probably the best high output baseboard you will find , 3 or 4 different piping options and very high output since you will be using hotter water to make the existing stuff perform . The panel rad option is a very good one and they really are not that damn expensive . Haydon and Slant Fin also make real high output baseboard but you are not gonna find it on the shelf at your local supplier usually .  I personally do not like the GV90+ , there are better options .  You should also have whomever is gonna do the work utilize Delta T pumps for your system as they will allow the installed radiation to utilize more of the heat before putting too hot water back to your boiler .  f you use the Smiths baseboard and it is piped with 2 parallel supplies you may be able to just replace the existing baseboard and not do too much work .  

nicholas bonham-carter

Cold in Vermont

It seems as though your first step would be to install the high output baseboard to the ground floor, and correct any boiler piping issues which you may have. Later you could change the boiler

I'm not sure with the amount of radiation you have that a mod-con boiler would be firing in it's most economical mode enough unless your radiation has a lot more capacity.

Why not have a look at Pexsupply.com for high output baseboard, and figure out what will fit, and then post once again here the new radiation edr's which you would have. Are the floors on separate zones? There would be a problem if not and you were using outdoor reset. Lochinvar has the"solution" boiler, which has outdoor reset options, and is lighter, than the standard cast iron. I suspect your old Peerless may have many years left in it.--NBC

JHR

Thanks and more info

Thanks for the comments guys. The smiths look interesting, I'll have to wait and see what he proposes. A delta T pump must regulate speed to achieve a certain return temp? Is that possible on a multi zone valve system? The runtal we had installed in the bathroom reno was an eye opening price adder, but worth it. Is there anythig specific you don't like about the GV+? I always wonder about a bolt on attachment vs a ground up redesign but they both seemed to really like it.

Which bring up another question that was asked. Our house has 5 zones from the boiler: DHW (priority), 1st floor, and 3 zones on 2nd floor (master bedroom and 2 baths, 2 bedrooms, and fourth bedroom).

Is it reasonable that the peerless is 85% efficient? I'm not sure how they energy audit determined that. Whether he measured it or he's going on how much propane we used vs heating degree days. If it's the latter it's probably wrong because we are pretty cold in the winter and not using as much fuel as you would normally expect. The desire to replace the boiler may be irrational at this point. We''ve always blamed the boiler as it's the heat maker. But after much recent research I know more about hydronic heating and realize the lack of radiation is likely more at fault. But, it's hard to let go of the "replace the damn boiler" mantra. If it would reduce (or maintain) the amount of propane we used and have us warmer it might be worth it anyway to do it all an just be done.

I have looked at pexsuppy, that's actually where the runtal came from. But I was also hoping some of you might have types you have used that I could specifically look for. Thanks again, keep the comments coming.