Looking for some advice from the pros- thanks in advance for your time.
I have a Carrier 58SX120 circa 1989 heating my 3700 sq ft house. We are looking at replacing it, and my HVAC guy has recommended an Amercan Standard variable speed 95 AFUE (AUY120). Now on really cold days I have felt that the Carrier hasn't kept some of the upstairs rooms of my house as warm as it should have. Unfortunately my house is not set up for zoned heating or multi units. So all that being said, here are my questions.
1. My understanding was that the Carrier had 120 BTU output, while the American standard has 120 BTU input. Do I have the Carrier info correct?
2. If my numbers are correct, would the Carrier still be expected to be putting out 120 BTU, or is efficiency lost over time?
3. Is the Amercian Standard an adequate replacement because of the 2 stage heating and variable speed, or am I going to be even colder if go ahead with the replacement? If not, what size unti should I be looking at?
It is all very confusing as a homeowner. I want t omake sure I've done my research before moving ahead with such a costly project. Thanks again for your time.