Lets say I had a 75,000 btu furnace installed in Pittsburgh pa. If a manual J was done and it stated a 60,000 would have been enough how badly oversized is this furnace.
I have a Rheem RGRK 2 stage furnace 75,00 installed and my house is 1800 sq feet living space. my neighbor is 1900 sq ft and recentlygot a trane xv 90 at 80,000 btu. Does my size sound right. I know a manual J is the only true way but looking for input. 4 contractors came to my house and estimate 70-80,000 depending on brand, bu tone said 60,000.