How do you read a Goodman AC serial number?
Goodman’s air conditioner warranty says the first four digits of the serial number, YYMM, show the manufacture date, and its furnace certificates say the same. Goodman’s technical bulletins list real serials whose build dates match: 1812154656 was built on December 11, 2018.
Sources: Limited Warranty, Models GLZS4B, GLZS5B, GLZS4M, GLXS3B, GLXS4B, GLXS5B, GLXS4M (PWGACHPR3BODB), checked October 19, 2026; SP-039 GPC1436H41DD and GPG1436040M41AB Serial/Rating Label, checked October 19, 2026.| Digits | What they mean | In 1812154656 |
|---|---|---|
| 1 and 2 | Year of manufacture | 18: 2018 |
| 3 and 4 | Month of manufacture (01 to 12) | 12: December |
| 5 to 10 | Production number | 154656 |
What will the home systems age report add?
The home systems age report will put your Goodman air conditioner or heat pump next to every other major system in your home, each with its build year, how long that kind of system typically lasts, and what to budget for replacing it.
Get the home systems age report
We’re building a home systems age report: your Goodman AC and every other major system, each with its age, typical life and replacement budget.
Where is the serial number on a Goodman air conditioner?
Goodman says the rating plate is generally slightly above the refrigerant valves, on the back of the outdoor unit. The serial is a 10-digit number, listed below the model number. An indoor coil or air handler has its own rating plate and its own serial.
What do some Goodman serial numbers decode to?
The first two rows are real serials from a Goodman bulletin, on packaged units, and the third is the example in Goodman’s warranty. The last two are made up to show the rule.
| Serial | Year | Month | Built |
|---|---|---|---|
1812154656 (from a Goodman bulletin) |
2018 | 12 | December 2018 (Goodman lists December 11) |
1804165082 (from a Goodman bulletin) |
2018 | 04 | April 2018 (Goodman lists April 11) |
Starts 2610 (Goodman’s warranty example) |
2026 | 10 | October 2026 |
2107000123 |
2021 | 07 | July 2021 |
2405456789 |
2024 | 05 | May 2024 |
How long do Goodman air conditioners last?
Goodman doesn’t publish a typical life in years. In its 2016 efficiency rule, the U.S. Department of Energy estimated average lifetimes of 21 years for central air conditioners and 15 years for heat pumps, across all brands.
Common questions about Goodman AC serial numbers
My indoor coil’s serial starts 1811 or 1812. Is it from 2018?
Maybe not. Goodman says a limited number of coils with an 1811 or 1812 prefix were actually built between January 2019 and January 2021. For other units, the first four digits are the build year and month.
Does this work on an older Goodman air conditioner?
The Goodman documents we cite go back to 2018. Older units may use a format Goodman doesn’t publish. Goodman’s customer support can date them from the model and serial number.
Why does the build date matter for the warranty?
Outside California, if the installation date can’t be verified, Goodman’s warranty treats the installation date as three months after the manufacture date in the serial number.