How old is my Carrier furnace?
Serial number age decoder for Carrier furnaces: 4 format eras, the decode rule in plain English, transcribed tables, and the official lookup.
Type the serial from the data plate, not the model number. Nothing is sent anywhere; the tables are in this page.
Format example: 4006A17330
- Carrier furnace serial numbers in the 1980 to present format encode the year as digits 3-4 (2-digit year; century by context, 1980+) and the week as digits 1-2 (01-53) (source: building-center.org).
- Example: serial 4006A17330 decodes to week 40 of 2006.
- Carrier furnace serial numbers in the 1980 to 1989 format encode the year as digits 1-2 and the month as digits 3-4 (source: building-center.org).
- Example: serial 850304091 decodes to March 1985.
- Carrier furnace serial numbers in the 1969 to 1979 format encode the year as digit 2 = last digit of year (1969-1979) and the month as letter 1 (A=Jan..L=Dec) (source: building-center.org).
- Example: serial A167890 decodes to January 1971.
- Carrier's official lookup at carrier.com returns current coverage status.
Format eras
- 1980 to present VERIFIED
####A#####digits 3-4 (2-digit year; century by context, 1980+) - 1980 to 1989 VERIFIED
#########digits 1-2 - 1969 to 1979 VERIFIED
A######digit 2 = last digit of year (1969-1979) - 1960 to 1979 VERIFIED
##A######first LETTER via table (L=1960 .. H=1979, cycles L-Z then A-H, skipping O, Q, Z)
How to read the serial
1980 to present formatVERIFIED
Shape ####A##### · example 4006A17330 · confidence high
- Year
- digits 3-4 (2-digit year; century by context, 1980+)
- Week or month
- week = digits 1-2 (01-53)
- Plant
- letter at position 5 (plant/line code; table not published)
Example: serial 4006A17330 decodes to week 40 of 2006.
1980 to 1989 formatVERIFIED
Shape ######### · example 850304091 · confidence medium
- Year
- digits 1-2
- Week or month
- month = digits 3-4
Example: serial 850304091 decodes to March 1985.
1969 to 1979 formatVERIFIED
Shape A###### · example A167890 · confidence medium
- Year
- digit 2 = last digit of year (1969-1979)
- Week or month
- month = letter 1 (A=Jan..L=Dec)
| Month code | Month |
|---|---|
| A | January |
| B | February |
| C | March |
| D | April |
| E | May |
| F | June |
| G | July |
| H | August |
| I | September |
| J | October |
| K | November |
| L | December |
Example: serial A167890 decodes to January 1971.
1960 to 1979 formatVERIFIED
Shape ##A###### · example 46U152456 · confidence high
- Year
- first LETTER via table (L=1960 .. H=1979, cycles L-Z then A-H, skipping O, Q, Z)
- Week or month
- week = leading 1-2 digits (1-52)
| Year code | Year(s) |
|---|---|
| L | 1960 |
| M | 1961 |
| N | 1962 |
| P | 1963 |
| R | 1964 |
| S | 1965 |
| T | 1966 |
| U | 1967 |
| V | 1968 |
| W | 1969 |
| X | 1970 |
| Y | 1971 |
| A | 1972 |
| B | 1973 |
| C | 1974 |
| D | 1975 |
| E | 1976 |
| F | 1977 |
| G | 1978 |
| H | 1979 |
Example: serial 46U152456 decodes to week 46 of 1967.
Where the data plate is on a furnace
Inside the furnace: remove the upper (burner) access door and look on the inside of the door, on the blower compartment wall, or on a sticker facing you at the burner deck.
General guidance, not brand-specific: the owner's manual or the installer can point to the exact spot. See the data plate guide.
For scale only: the InterNACHI Standard Estimated Life Expectancy Chart for Homes lists Furnace at 15 to 25 years of expected service (nachi.org). That chart is a guideline, not a prediction for your unit.
Open the official Carrier lookup takes serial number; returns current coverage status; URL verified live
This site is a reference built from published tables. The manufacturer's own lookup wins whenever the two disagree.
Sources
- https://www.building-center.org/carrier/
- https://www.building-center.org/bryant-hvac-age/
- https://www.carrier.com/residential/en/us/warranty-lookup/official
Frequently asked questions
How do I tell the age of a Carrier furnace from the serial number?
In the 1980 to present format the year is digits 3-4 (2-digit year; century by context, 1980+) and the week as digits 1-2 (01-53). Example: serial 4006A17330 decodes to week 40 of 2006.
Where is the serial number on a Carrier furnace?
On the data plate. Inside the furnace: remove the upper (burner) access door and look on the inside of the door, on the blower compartment wall, or on a sticker facing you at the burner deck.