Fix it
Why does my pilot light keep going out?
A standing pilot that will not stay lit is nearly always a conversation between the flame and the thermocouple that watches it. The thermocouple only holds the gas valve open while it feels heat — no heat, no gas, no pilot.
What it usually is
-
A worn-out thermocouple
After years in the flame, the tip generates too little voltage to hold the valve. The pilot lights while you hold the button and dies moments after release — the classic pattern.
-
A lazy, yellow pilot flame missing the sensor
Dust in the pilot orifice weakens the flame until it no longer wraps the thermocouple tip. A healthy pilot is steady blue; a wavering yellow one is starving.
-
Drafts snuffing the flame
A pilot that dies on windy days, or when a nearby door slams, is losing to airflow — often down the flue or through a damaged burner-compartment cover.
-
A failing gas valve or low supply pressure
If a new thermocouple and clean orifice do not hold it, the valve electromagnetics or supply pressure are suspect — pro territory.
Safety first: If you smell gas near the appliance, do not relight anything. Leave the area and call your gas utility.
What you can check yourself
Relight per the label instructions, holding the button a full 30 to 60 seconds. Observe the flame: blue and wrapping the thermocouple tip, or yellow and shy? A thermocouple is an inexpensive standard part many owners replace themselves — gas off first, and match the length.
When it’s a job for a pro
A pilot that fails after a new thermocouple, or any smell of gas around the appliance, needs the valve and pressure tested. Chronic draft blowouts justify checking the venting rather than just relighting.
A thermocouple is $10 to $25 as a part; having it replaced typically runs $100 to $250. Gas-valve replacement is more substantial at $300 to $600.
Ready for a heating technician? Get matched now
Enter your ZIP and we match you with an independent local partner for exactly this kind of job.