Where to look: Rating plate on the side of the tank jacket. Read it from the outside. If the label isn’t visible without removing a panel, don’t open the unit; use the installation paperwork or ask the installer.
Decode a American Water Heater serial number
How to read a American Water Heater serial number
YYWW… The first two digits are the year and the next two the production week: YYWW. Example 9746… = week 46 of 1997.
| Example serial | How it reads | Built |
|---|---|---|
9746123456 | 97 = 1997, 46 = week 46 (November) | Week 46 of 1997 (around November) |
2214A001234 | 22 = 2022, 14 = week 14 (April) | Week 14 of 2022 (around April) |
- The Energy Trust of Oregon decoder (opens in a new tab) uses 9746… as its example: the 46th week of 1997.
- Before the 2000s American built heaters for many store and hardware brands. If your label names American Water Heater as the maker, this code usually applies even when the front of the tank shows another name.
- Read the week as a season: week 1–13 is the first quarter, week 40–52 the last.
Format source: Energy Trust of Oregon: water heater serial number decoder (PDF) (opens in a new tab); also InspectAPedia: American water heater age (opens in a new tab).
What to do with the date
- Check the warranty. Enter the serial number in the American Water Heater warranty verification (opens in a new tab). Coverage depends on the model and the build or installation date.
- Weigh repair against replacement. Age is one factor; leaks from the tank, rusty hot water and repeated failures matter more. See how long water heaters last and the repair-or-replace notes on the main decoder page.
- Troubleshoot by brand. Our American Water Heater guides cover codes, lights, leaks and no-hot-water problems.
Common questions
My tank says ProLine. Is that American?
American ProLine is an American Water Heater line, so the year-week code applies.
Could 0812 be December 2008?
No. The second pair is a production week, so 0812 is week 12 of 2008, around March.
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