I am thinking about getting a new furnace this year but want to try to estimate my energy savings. Can somebody confirm the age and efficiency of my current furnace?
HEIL model # GL-175LG-7CR
Serial # of H64862309
Input Rating: 175,000 BTU/HR
Bonnet Cap: 140,000 BTU/HR
One contractor told me it is from '76 while a couple of others said '86. Regarding efficiency, most have told me it is around 60%. How does bonnet capacity relate to the AFUE rating?