Age conformation

I need help on identifying the age of a furnace. Do you read the ser. # what numbers do you look for.

Depends on brand. Post the info here and someone will have the info for you. Brand, Serial and Model if you have it. Usually doesn’t take long. The folks here on the board are great at helping each other.


AirTemp Ser.#GN568769 These are the only numbers I have the mod. # was not legible.

Different furnaces some the first two # some the second 2 # Check the fan you can some times get it from the Green housing . Check the transformer , check the bottom of the plate that has the info it is some times there example mar 23 1965 .How old is the home more clues 18 years old furnace could also be that age 10 years furnace is usually that age. Is it Gas a or oil .
When asking a question try and give us as much information as possible .
How old is the Air Cond. furnaces frequently are the same age also.
Furnace name you can check their web site .
sounds like 87 what year is the home if 87 then pretty good idea
Roy Cooke

House was built in 1978

I believe it to be May of 78. Apparently on these it goes by the first two letters - GN.
I sent you a pm regarding possible heat exchanger problems with these.

As Keith said, the first two digits, GN, are secret code for May 1978.