News & FAQ

How to Clean a Pilot Light


Valerie Johannsen People & Brand Manager

Wondering how to clean a pilot light or why you might need to in the first place? While many pilot lights are being replaced with an electrical spark, older furnaces still use them.  A pilot light is an ever-burning gas flame built into your furnace to light it when heat is necessary.  Since the pilot light has a constant flow of gas to it, if it ever extinguishes, you would find yourself with a gas suffocation problem.  To resolve this, a handy device known as a thermocouple holds the gas-valve open while heat is applied.  The burning pilot light generates electricity via the thermocouple to keep the gas feed active.  If the pilot light goes out, electricity ceases and the valve is shut, stopping the flow of gas.

Sometimes you’ll find that the pilot light and the thermocouple have gained substantial carbon and soot deposits.  With a heavy enough level of detritus, it can impede the thermocouple’s ability to heat up, preventing the pilot light from staying lit. When that happens, it’s time to clean things up.

What You Need

  • Wire Brush
  • Metal File
  • Pliers or Wrench
  • Cloth or Compressed Air

How to Clean a Pilot Light

  1. Cut off the gas to your furnace. There should be a master valve near your furnace. Switch it off and wait a few minutes for the gas to dissipate.
  2. Remove the pilot light and thermocouple assembly. When you open the furnace, you should see a small bracket holding the pilot light and thermocouple. Older models require the full assembly to be pulled out, while newer furnaces can simple have them removed individually.
  3. Use your pliers or wrench to remove the pilot light and thermocouple from the bracket.
  4. Using the wire brush, brush away the carbon buildup and soot from both components.
  5. For hard to reach areas and stubborn buildup, use the metal file.
  6. Wipe away dust with a soft cloth or burst of compressed air.
  7. Return both components to the bracket and reinstall the assembly.
  8. Test the pilot light.

If the furnace still refuses to light after you’ve turned the gas feed on, or you smell gas leaking out, shut off the valve and call for a repairman, as the problem is elsewhere and will require further troubleshooting.

Heating and Cooling Des Moines Since 1997

At Service Legends, we take pride in heating and cooling Des Moines and the surrounding areas. Our HVAC services include furnace and air conditioner installation, repairs, maintenance, and tune-ups. Our lineup of Indoor Air Quality solutions includes whole-home humidifiers, air purifiers, and air filtration systems. We can even help with HVAC financing.

Call 515-657-6634 to contact our Home Comfort Heroes today. We’re standing by 24/7.

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