Why Does My Pilot Light Keep Going Out?

Blue gas flames of a water heater pilot light.

The most common reason that your pilot light on your water heater keeps going out is a damaged, bent or dirty thermocouple.  

What is a thermocouple?

A thermocouple is a device that measures temperature. More importantly it is the device that regulates the gas flow inside your water heater or furnace. It has two wires. One sits hear the thermostat and the other sits by the pilot light flame. If the temperature goes up the thermocouple sends and electric signal that opens the gas valve and allows for the combustion to take place. If the pilot light goes out, the thermocouple senses the drop in temperature and signals for the gas valve to close.

What Might Cause a Faulty Thermocouple?

If you have a faulty thermocouple is the most common reason that your pilot light is malfunctioning. Over time your water heater will collect dirt, dust and other kinds of debris. Build up on your thermocouple can cause a malfunction. This is and easy fix; simply let it cool down and brush off the dirt or debris. Your thermocouple might bend. The end that sits near the pilot light flame is what communicates with the gas valve and tells it to open or close. If it is bent away from the flame it won’t register heat and will keep the gas valve closed. Again simply wait for you water heater to cool down and then bend it back.

If you are unsure how to proceed, do not attempt a repair yourself, call us and let one of our professional technicians repair the issue. If your thermocouple is neither bent nor dirty, you may have a damaged or malfunctioning product. Call Kliemann Brothers today or request service online to find out about replacing your thermocouple. If it is not a thermocouple problem it is possible there is a dirty pilot light opening. This causes the pilot flame to cool down and thus will not warm the thermocouple effectively.

Hot Water Heater Problems?

Contact Kliemann Brothers today at 253-537-0655 or request service online if you suspect either of these issues and one of our certified technicians will assist you.

Need HVAC Service?

Contact Kliemann Brothers today.

CALL US AT 253-537-0655


Kliemann Brothers proudly provides HVAC service to Bonney Lake, Burien, Covington, Des Moines, Enumclaw, Fircrest, Gig Harbor, Kent, Port Orchard, Puyallup, Renton, Steilacoom, Tacoma, University Place, and the surrounding communities. Visit our service area page for more coverage details, call us at 253-537-0655, or request service online today.