How old is my Coleman?
Type your Coleman serial number below to get the month and year it was built. 2 documented Coleman serial formats, covering 1971 to today.
Coleman, York and Luxaire are all Johnson Controls brands and share one serial format.
The serial number is on the metal rating plate. On a furnace it is usually inside the front door on the side wall; on an outdoor AC or heat pump it is on the back or side of the cabinet, near the refrigerant lines.
Type the Coleman serial exactly as printed. Spaces, dashes and lowercase are all fine.
Coleman serial number formats
Post-October-2004
2004 to present
The year is split in two: the 2nd and 4th characters are its digits, with the month letter sitting between them as the 3rd character.
W0K5896070 reads as September 2005
Source: Building Intelligence Center · checked 2026-08-25
Four letters plus six digits (1971 to Oct 2004)
1971 to 2004
The 2nd letter is the month and the 3rd is the year, but the year letters repeat on a 21-year cycle, so most letters mean two possible years. We show both rather than guess.
WAKM011379 reads as January 1980 or January 2001
Source: Building Intelligence Center; HowToLookAtAHouse.com (licensed home inspector) · checked 2026-08-25
Where to find the serial on a Coleman
- Gas furnace: open the front door. The rating plate is on the inside side wall, usually near the top.
- Outdoor AC or heat pump: a metal or foil plate on the back or side of the cabinet, near where the copper lines enter.
- Mini-split: on the side of the outdoor unit, and on the indoor head behind the front flap or on its right side.
- Photograph the plate rather than copying it by hand. Misreading 0 for O, 1 for I or 5 for S is the most common reason a lookup fails.
Same serial format
These brands come off the same lines and decode identically:
Is your Coleman showing an error code?
Age tells you where the unit sits in its life. The fault code tells you what is wrong right now. We have 47 Coleman codes, each quoted from the manufacturer's own manual.
HVAC Code Lookup publishes these decoding rules from public industry references, not from Coleman. If the rating plate prints an explicit manufacture date, trust the plate over any decoder.