Furnace Age Help Comfortmaker

Comfortmaker With an RPJ Heat Exchanger

Model G-U 400100-12M-P
Serial # 0000211401-L26-009

This is what I have.
I think Tallen posted it.

Comfortmaker (International Comfort) uses the first letter for the month
(skipping I) and the first two digits are the year.

So could be 2000

It says to use the first letter followed by 9 numbers. I see no letters
There is excessive rusting for it to be a 2000 I think

Thats all I have, and figured the first 0 might have been a letter.

You could try the site called furnace compare

I’ll Try that thank you


Your serial number appears to be backwards. Perhaps a newbie serial number stamper at the plant who didn’t know better. Wouldn’t be the first time I’ve found that.

If I reverse the serial number to 009-L26-0000211401, then it matches the Comfortmaker serial numbers I have in my file, seeming to indicate a November 1992 or November 2002 unit. It wouldn’t be 1962, 1972, or 1982 because they used a different serial number system in those years.

Combine that with construction date of the house or manufacture date of other appliances and see if you can match it up.

Thanks for your input Russel.
The house was built in 1950 there are moisture issues in the basement and there is 3/8 of an inch of rust right outside burner tubes with 1/4" layer inside the tubes.
The report has been sent I had to write unable to termine the age.
Clearly its time for a new heat exchanger at least if not a new furnace.