What Causes a Pilot Light to Go Out?: 1 Minute to Understand Common Reasons

A pilot light is a small, continuously burning flame used to ignite the main burner in gas appliances such as furnaces, water heaters, or fireplaces. Its reliable operation is critical for both safety and functionality. But what causes a pilot light to go out? Common culprits include a faulty thermocouple, drafts or sudden gusts of air, dirty or clogged pilot orifice, and interruptions or drops in gas supply pressure. The thermocouple—a sensor that monitors the pilot’s heat—will cut off the gas if it senses the flame has gone out, preventing leaks. Even slight shifts in air pressure from open windows or nearby fans, or natural wear and tear on appliance components, can disrupt the delicate flame. Regular maintenance, such as cleaning the pilot orifice from dust buildup, helps prevent these issues and ensures household safety.

Tips 1:

From my perspective as a designer, ensuring your utility and mechanical rooms are well-ventilated and unobstructed improves appliance performance and safety. When planning a home layout, positioning utility spaces away from direct drafts and heavy foot traffic can help minimize unexpected airflow that may extinguish a pilot light. Detailed layouts—especially those created with advanced home designer tools—make it easy to optimize both form and function during your renovation or new build.

FAQ

Q: Can a bad thermocouple cause a pilot light to go out?

A: Yes, a faulty thermocouple cannot detect the heat from the pilot flame, causing it to shut off the gas supply as a safety measure.

Q: Is it dangerous if the pilot light keeps going out?

A: Frequent outages should be investigated. While safety systems prevent gas leaks, repeated extinguishing could signal a bigger issue that should be fixed promptly.

Q: Can drafts blow out a pilot light?

A: Yes, strong or sudden drafts are a common reason for pilot light failure, especially if equipment is near doors or windows.

Q: How do I know if my gas supply is the problem?

A: If multiple gas appliances are affected, or there is no hissing sound when you try to relight, contact your gas provider for troubleshooting.

Q: Should I relight a pilot light myself?

A: While it’s often safe if you follow manufacturer instructions, call a professional if you smell gas, have recurring outages, or are unsure about the process.