Both SteveF and TampaAC info is right, if you go the the energy star web site and look under FAQ most of your answers are there. However it looks to me like 80% or 90% less than 95% would still get the credit if they have a "advanced main air circulation fan" aka variable speed. I have been trying to nail this down with my suppliers and manufactures and there is a lot of confusion on this. Does anybody know.....and I mean know for sure.
yeah, i had someone else say they thought it was only with 90% furnaces today. but i have had people here say that with an 80% variable speed then it will qualify. I think there is still a little bit of confusion as you said. i dont think the links provided make it perfectly clear.
It looks like a loop hole to me. Hey all the rich fat cats get plenty of loopholes, why not the rest of use average joes. IMO, Unless they change their website, I plan to submit my 80% VS furnace for the tax credit next year. In my case, the 30% credit is more than the increased cost of going from a single stange Trane XR80 to a 2 stage XV80.