A.O. Smith / State · Water Heater error code

1 flash (every 3 s)Normal: pilot lit, control OK

Cross-checked Power off, standard tools

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Related diagnostic guides

Guide · Water Heater

Gas water heater: pilot won't light or won't stay lit (diagnose and refer)

Standing-pilot gas tanks use a thermocouple or thermopile heated by the pilot to hold the gas valve open; FVIR models add a thermal switch and flame arrestor. This is a gas appliance: the tech's role here is to read the status light, confirm gas supply, note symptoms and hand off. Pilot assembly, thermocouple/thermopile, burner and gas valve work go to a licensed plumber or gas technician.

5 steps ~20 minadvanced

Guide · Water Heater

Water heater: water too hot or ECO keeps tripping

On electric tanks overheating usually means a thermostat welded closed or not clamped tightly against the tank, or a grounded element heating outside thermostat control. On gas tanks it is a gas control fault and must be referred. Treat it as a safety call: overheated water is a scald and tank-pressure hazard.

6 steps ~45 minmoderate