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.
Cross-checked ~20 min advancedBrands: All
Before you start
- GAS: if you smell gas, do not light anything or operate switches; leave the building and call the gas utility or 911
- No repair procedure is given here for the gas valve, pilot, burner, venting or gas pressure: refer to a licensed plumber/gas technician
- A heater that keeps shutting off can be a venting or CO problem: make sure CO alarms work and ventilation is not blocked
- Many jurisdictions require a permit and a licensed installer for any gas-side work
Diagnostic steps
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