Laundry room with a tank-type water heater beside the washer

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Water heater: identify the OEM from the rating plate

The plate gives three clues: the builder line or plant city, the serial style, and the model pattern. Two of the three agreeing identifies the family (A.O. Smith, Rheem or Bradford White, plus GE's own plant since 2022).

Cross-checked ~5 min easyBrands: A.O. Smith, State, American, Reliance, Whirlpool, Kenmore, Rheem, Ruud, Richmond, GE, Bradford White, Jetglas

Before you start

Do not remove the burner access or element covers just to read the plate.
Gas valve, burner and venting work is blocked: diagnose and refer.
Electric tank: 240 V behind element covers; power off before opening.

Diagnostic steps

Unlock all 5 steps with expected values

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