Tank Water HeaterTroubleshooting2026-01-26
Water Heater Pilot Light Keeps Going Out
A pilot that won't stay lit usually means a dirty or failed thermocouple — or a draft.
On a gas tank water heater, a pilot that won't stay lit is a common and often inexpensive fix.
The usual cause
The thermocouple senses the pilot flame and shuts off gas if it goes out. A dirty or failing thermocouple is the most common reason a pilot won't stay lit.
Other causes
A dirty pilot orifice, drafts, a clogged flame-arrestor screen at the base, or a faulty gas control valve can also cause repeated pilot outages.
Key takeaways
- A failing thermocouple is the top cause
- Clean the base flame-arrestor screen
- Rule out drafts near the unit
- Don't keep relighting repeatedly
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Licensed, gas-certified technicians serving Greater Vancouver since 1999. CombiBoiler.ca — A division of ROMA Heating Ltd..
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