Water Heater Pilot Light Keeps Going Out: Causes and Fixes

What are the 4 causes of a pilot light that keeps going out?

The 4 causes of a pilot light that keeps going out are listed below.

• A worn thermocouple fails to sense the flame and shuts off the gas.
• A dirty pilot tube makes a weak flame that goes out.
• A draft from a vent or open window blows the pilot out.
• A faulty gas control valve cuts the gas to the pilot.

Is a pilot light that keeps going out dangerous?

No, a pilot light that keeps going out is not dangerous while the thermocouple shuts off the gas, but a gas smell near the water heater is an emergency.

What should you do when the pilot light keeps going out?

The 4 things you should do when the pilot light keeps going out are listed below.

1. Follow the relighting steps on the water heater label once.
2. Check for drafts near the burner door.
3. Leave the house and call the gas utility when you smell gas.
4. Call a plumber when the pilot goes out again.

When should you call a plumber?

You should call a plumber in the 4 situations below.

• The pilot goes out again after relighting.
• The flame is yellow instead of blue.
• A gas smell is present after the utility clears the area.
• The gas control valve does not respond.

Related plumbing problems and next steps

How much does the plumbing repair cost?

The plumbing repair cost depends on the part: a thermocouple replacement costs about $150, according to HomeAdvisor. Water heater repair prices and local plumbers are on the water heater repair in the Lancaster area page.

What is a related plumbing problem?

A related plumbing problem is no hot water in the house, and the no hot water in the house guide lists its causes and first steps.

Written and fact-checked by the Lancaster PA Plumbers editorial team using HomeAdvisor, EPA WaterSense and City of Lancaster data. Last updated October 29, 2026.