age please

Lennox condensor
m/n 13ACD-036-23-01
s/n 5806A01254

Lennox furnace
m/n G4ouH-48B-090-11
s/n 5905MU3387

Courtesy of David Valley.

Lennox: Either the first two or second two digits are the year, it varies by era, but most of them actually have a separate sticker somewhere that has the year printed on it. Newer ones are first two equals manufacturing plant #, 2nd two are year and letter in fifth slot is month (A thru M minus I). So 5898G 07568 would be Plant # 58, Year of MFR would be 98 and month would be July.

thanks dale

That applies for equipment manufactured around 1974 and later. Prior to 1974, the first two digits will be year, and the third-fourth digits the month:

672 = February 1967
6911 = November 1969
723 = March 1972

Schlennox stuff doesn’t last 32 years! :mrgreen: :mrgreen: :mrgreen:

Unless I’m completely brain dead tonight, what you are saying does not correspond to Prestons Guide. For the above mentioned furnace in Earls post Prestons guide puts it at '00. However the serial number would indicate that it is '05. Can anyone enlighten me?

toss your prestons guide;)

How did Prestons Guide come up with 2000?

I have the prestons on cd-rom, so I can just type in the Model # and it goes to the listing of lennox units which shows '00-'01.

I cannot find it in the preston guide

Do you have the book or cd?

Robert I couldnot find it in the preston guide

in almost all cases the serial# will give you the age of the units not the model#.prestons is not always right.always check this board for answers;)