I'm a first-timer here, so bear with me.
We live on a windy mountainside in Western North Carolina, and I want to replace a propane furnace and electric air conditioner with a heat pump and a propane furnace. I've gotten three estimates that have left me comparing apples and oranges. Only one contractor has done anything approaching a Manual J heat calculation, but one of the others says he'll do one after I sign a contract and before he brings the equipment.
All three estimates treat the heat pump as an add-on to the propane furnace, and I think it ought to be the other way around. Two of the three are proposing 92% AFUE two-stage, variable speed furnaces; the third is proposing a 92% AFUE one-stage, single-speed, but it appears to be a builder's model.
All are quoting 13 SEER heat pumps, but one also is offering a 15 SEER HP for only about $300 more. I could get that difference back from the 2009 federal tax rebate.
What I'm proposing to do is to ask all three to give me estimates on a 15 SEER, 9 HSPF HP, which qualifies for the federal rebate, and a 92% one-stage furnace. My thought is that the furnace would kick in at an outside temperature (35 degrees or so) where it would have to run at or near full tilt anyhow, so the lower stage wouldn't be of much benefit.
Does this make sense, or am I off base?
Thanks for your input.