In the past several months I've gotten three estimates on an AC system for our house.
We have a 2100 sq ft, two level house with one skylight in the Portland Oregon area. It does get hot here, but we have relatively short summers. For each estimate, the proposed system was different:
1) XB13 2.5 TON 13 SEER X8 TRANE CONDENSER 410A
2) XR13-024 2 TON TRANE AC
3) XB13 3 TON 13 SEER X8 TRANE CONDENSER 410A
Are these all equivalent? Why is the tonnage different on every one? When would a heat pump makes sense? We have a 13 year old lennox gas furnace. I think it's one of the 80% efficiency level units (not sure if my terminology is correct). Just don't know what my next step should be.
Thanks in advance!