Why Won’t My Furnace Pilot Light?

October 3, 2022

Waking up on a cold morning to an even colder house is less than ideal and can be a sign that your furnace stopped working at some point during the night. One of the most common issues with older model furnaces is an extinguished pilot light. While a one-time occurrence is no cause for alarm, if the pilot light goes out repeatedly or refuses to stay lit, further investigation is required. Once you’ve determined the source of the problem, you can make an informed decision on whether to call for emergency service or solve the issue yourself.

What Is a Pilot Light?

A gas furnace pilot light is a continuously burning flame. Its main function is to ignite the burners when the furnace is called upon for heat. The thermocouple assists with furnace operation by monitoring the presence of the flame and turning off the gas supply to the pilot light if it should become extinguished or becomes weak.

4 Common Reasons Your Furnace Pilot Won’t Light

There are several reasons why your gas furnace pilot won’t light: an ongoing draft, a faulty thermocouple, an accumulation of dirt, or an inefficient supply.

Ongoing Draft

Over the years, your pilot light may blow out periodically due to a strong draft during storm activity or during times when there’s a high wind. However, if this occurs on a routine basis, it may be caused by a leak in the output duct of the furnace.

Faulty Thermocouple

If the thermocouple is malfunctioning, it may be unable to detect the flame and close the gas valve in response. Reasons for the malfunction include:

  • A broken thermocouple
  • A dirty thermocouple
  • A misaligned thermocouple

Accumulation of Dirt

It’s important to keep all your HVAC components clean for safety and efficiency, including the area surrounding the pilot light. If dirt is accumulates in the intake valve, oxygen levels that are needed to keep the pilot light burning strongly will be reduced. You can prevent this by scheduling routine furnace maintenance each fall, during which a skilled technician will inspect, clean, and tune your furnace to ensure its reliable, efficient operation throughout the heating season.

Inefficient Supply

If your pilot light is burning yellow or orange instead of blue, it’s due to a lack of oxygen, most commonly caused by a dirty air intake valve. Because fire needs fuel and oxygen to burn, an inefficient supply of oxygen causes the flame to become weak. While a blue flame produces an adequate amount of heat to trigger the thermocouple, a yellow flame does not, causing the thermocouple to turn off the gas valve and your furnace to stop working.

If you’re located in the Bainbridge or Thomasville area and have questions about your furnace, you should contact Harrell King Heating & Air! Our HVAC experts in Southwest Georgia are ready to help with all of your heating and cooling needs. Call 229-243-8040 today!

Furnace Repairs in Bainbridge & Thomasville, Georgia

The team of experienced professionals at Harrell King Heating & Air has provided homeowners in the southwest Georgia area with expert furnace repair, maintenance, and installation services for more than three decades. We offer 24/7 emergency service so you’re never left out in the cold, and treat all our customers like family — with honesty, respect, and fair pricing.

If your gas furnace will not ignite, call Harrell King today at 229-243-8040, or contact us online and let us know how we can help.

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