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Why Won’t My Water Heater Pilot Light Stay On?

If your water heater pilot light won’t stay on, you may be wondering what the problem could be. This is a common issue, and there are several things that you can do to troubleshoot it.

There is nothing more frustrating when trying to run a hot bath than when your water heater keeps turning off. If your water heater pilot light will not stay lit, it is important to fix it immediately. There are many reasons your water heater pilot light might turn itself off.

What is the Thermacouple?

Often, when your water heater won’t ignite, it’s due to the thermocouple. 

The thermacouple is a safety device that is located near the pilot light on your water heater. Its purpose is to shut off the gas flow to the pilot light if the pilot light goes out. This prevents the buildup of dangerous gases in your home.

One of the most common reasons why a water heater pilot light won’t stay lit is because the thermacouple is not working properly. If the thermacouple is defective, it will not be able to sense when the pilot light goes out and will not shut off the gas flow. As a result, the pilot light will go out and you will have to relight it.

This device detects whether your pilot light is on by generating a heat-powered electrical current. If the thermocouple has cooled, it assumes that your water heater pilot light is off and your water heater won’t ignite. A faulty thermocouple can cause problems with your water heater not staying lit.

Reasons that Water Heater Pilot Light Won’t Stay On

  • Dirty thermocouple: If you can light your pilot light, but the water heater pilot keeps going out, there are many possible causes. One of them is a dirty thermocouple. When you have a problem with your water heater not lighting, look at your water heater pilot light. Inspect the thermocouple to determine if it is dirty. If so, turn off the gas and allow the thermocouple to cool, then clean it by gently sanding with fine sandpaper. Then turn the gas back on and attempt to light the pilot.
  • Bent thermocouple: Sometimes, when your gas water heater won’t stay lit, if you check the thermocouple, you may see that it has been bent. This will prevent the pilot light from heating it. This will cause the thermocouple to turn off the supply of gas, and then your water heater won’t light. To avoid your water heater going out, bend the thermocouple so it is closer to the pilot light.
  • Dirty pilot tube: Sometimes, your gas water heater won’t light due to a dirty pilot tube. Use a needle to remove any blockages when the pilot tube has cooled.
  • Damaged thermocouple: If none of these techniques work, it is possible your thermocouple is damaged and needs to be replaced or repaired.

For help getting your water heater running, contact the experts at Clear Drain Plumbing today!

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