How old is my Carrier?
Type your Carrier serial number below to get the month and year it was built. 2 documented Carrier serial formats, covering 1980 to today.
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 Carrier serial exactly as printed. Spaces, dashes and lowercase are all fine.
Carrier serial number formats
10-character WWYY
1980 to present
Digits 1-2 are the week and digits 3-4 are the year. The letter is the plant code and the last five digits are the sequence number.
4006A17330 reads as week 40 of 2006
Source: Building Intelligence Center; Dr. Ray Franco, PhD, PE (electrical-forensics.com) · checked 2026-08-25
9-digit all-numeric (BDP era)
1980 to 1989
Nine all-numeric characters: digits 1-2 are the year and digits 3-4 the month. Used mostly on 1980s Bryant and BDP equipment.
850304091 reads as March 1985
Source: Building Intelligence Center · checked 2026-08-25
Where to find the serial on a Carrier
- 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 Carrier 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 28 Carrier codes, each quoted from the manufacturer's own manual.
HVAC Code Lookup publishes these decoding rules from public industry references, not from Carrier. If the rating plate prints an explicit manufacture date, trust the plate over any decoder.