Thank You forum for helping me out, Finally got heat loss calc from contractor, 74000. He suggested a40000/73000 92.5 2 stagexl 90 and a large flow thru humidafier for my old ranch home in buffalo ny. Ive read a lot of your posts and have heard comfort rather than efficiency with 2 stage model. I have long runs un my home will 2 stage 80 or 2 stage 90 be best for me thank you all again, any suggestions will be greatly appreciated.