Gas-fired Replacement Furnace

Overwhelmed

I've been researching a replacement furnace and domestic hot water system, and it seems that every time I feel ready to decide, I find a whole new direction to go in...  I have a cape with cast radiators that was way over-built (needs about 136k btu's).  I would love the most efficient system, but I also want the longest lasting with low maintenance costs (sounds like a pipe-dream, I know).

Of the quotes I've gotten, 2/3 contractors have quoted me a Buderus GB142, only to tell me that I shouldn't expect it to last.  One has quoted me a Burnham ES2, but I've read many horror stories about failures and cracks and I've read here on the wall that a mod/con will be much more efficient for my situation.

Is there a right answer?  I've looked at 'Ray', Veisman, and Munchkin boilers online as well, which all sound promising, but I haven't found any local (central CT) contractors who install or service them. The cast iron/stainless/aluminum arguments seem un-ending on the mod/cons, and I still don't know if they will save me that much in the long run anyway!

Another question I can't find the answer to is- do these mod/cons use a lot of electricity for their ignition and pump systems?

 

Jean-David Beyer

I also have a cape cod house.

It has about 750 square feet downstairs and is heated radiant in-slab. Upstairs is about 450 square feet and is heated by fin-tube; I have put 14 feet of Slant/Fin upstairs which is way too much if you put 180F water in there. I figured I needed about 23,000 BTU/hr upstairs on a 0F day downstairs and 6,500 BTU/hr upstairs. Upstairs and downstairs are (now) on separate zones. I have lots of insulation and fancy Marvin windows.



I am astonished you say you need about 5x the heat I do. Have you no insulation and single-pane windows? Do you keep it unusually hot inside? Is you house a cape cod in name only, but actually extremely large? Are you designing for an unusually cold day?



I have 4 Taco 007 circulators, of which at most 3 can run at a time. These are nominally 1/25 horsepower or 30 Watts each. But if you multiply the volts x amps, you get about 86 watts each. I advise using the higher number. So if three circulators ran all the time you would be using about 260 watts. With a good outdoor reset, some people actually recommend running the circulators all the time. I have outdoor reset, but I have never run it during the winter yet, so I do not know how I will let the circulators go. I think I want the downstairs to run at least 1/2 the time, and I do not care much about the upstairs. So the boiler circulator will run whenever either upstairs or downstairs or both want heat. Otherwise, it will not run. And if the indirect water heater wants heat, only the DHW circulator will run. The DHW runs very little.



As far as the spark ignition, it probably runs as much as a Beckett oil burner sparker runs; i.e., whenever it is firing. How much could that be? 5 or 10 thousand volts, 5 ma? 50 watts? You do the math. But unless you run one of those hot surface ignitors used in gas furnaces, I think you are stuck with that. But the heat from that 50 watts will also heat the water in the boiler, so it is not wasted.



My boiler is Weil-McLain and has an aluminum heat exchanger. I have heard all the debates, found them inconclusive, and decided to go with the contractor in this issue and hope for the best. Maybe they will save money, maybe they won't. They will save gas and help a little with the environment.