I am planning a conversion from oil to
gas. I have bids from three contractors with three different boilers and three
different heat load calculations. They are all experienced and the price difference
among them is very small.
The house has two stories, about 2000 sq.
ft., 2/3 of it is 170 years old (assumed uninsulated) and 1/3 is 35 years old
and insulated. It has a rubble foundation and dirt floor where the boiler will
The old part of the house is heated by
steam, the newer part by FHW through baseboards. A Burnham V8 series oil fired
boiler services both zones as well as the indirect water heater. The baseboard
loop is fed from a tankless coil in the boiler, so it is clean. As with many of
its ilk, the boiler is leaking water, but I have managed to limp though most
of our northeast winter with it.
I am planning to replace the
8 single pipe steam radiators (in 7 rooms) with Ecostyle panel radiators and replace the
boiler with a high efficiency gas condensing boiler. The three proposed boilers
are Viessmann Vitodens 100-W, Lochinvar Knight 155K btu and Weil-McLain WM97.
All three contractors did heat load calculations, but the results show as much
as a 50% variation in some rooms.
Are there some criteria I can use to
evaluate the bids?
Is there a clear preference among the
three proposed boilers?
Is it important that the installer
also service the boiler in future years?
Thanks for any guidance you can
This post was edited by an admin on March 25, 2013 3:13 PM.