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Your pilot light went out. Don’t worry you’re not alone. This is one of the most common problems that can happen to older gas furnaces. So what exactly is a pilot light, why did it go out, and how can you re-light it? We’ll cover these questions and more below.
What is a pilot light?
A pilot light is a small flame that is used to ignite the burners in older gas furnaces. (Newer furnaces use an electric igniter)
Why did my pilot light go out?
There are several reasons why your pilot light may have gone out:
Weak burning flame- Your pilot light should be burning bright blue. If it turns yellow then something is causing the flame to burn inefficiently. Your thermocouple should detect this and shut off the gas valve to your pilot light.
Thermocouple malfunction- Dirt can build up in the intake valve and restrict the amount of oxygen that is required to keep the pilot light burning efficiently.
Draft- Believe it or not your pilot light can go out when there is a strong draft around your furnace.
How to re-light a pilot light on a gas furnace
Most furnaces have instructions attached to them. It is highly recommended to turn to your furnace’s owner’s manual and follow the manufacturer’s instructions.
If instructions are not present this is the general procedure that you can follow:
Step 1: Find the pilot light assembly. It’s usually near the bottom of the furnace and has a gas valve with on, off, and pilot settings.
Step 2: Turn the valve to off and wait three minutes. No tools should be required to do this. You should be able to turn the knob with your fingers. DON’T SKIP THIS STEP. Turning the valve off stops incoming gas flow but it does not stop the gas that was already emitted. Waiting three minutes lets the gas dissipate.
Step 3: Switch the valve to the pilot setting. Hold the lighted match to the pilot opening while you push reset on the pilot control panel. Keep this button depressed until the pilot flame burns brightly. Lastly, set the valve to the on position. The furnace should start automatically.
Step 4: Wait to see if the pilot light stays on. If the pilot light won’t stay lit, the opening may be clogged. Turn the gas valve off, and clean the opening with a piece of fine wire. If it still won’t stay lit after several attempts, you may have a faulty thermocouple.
If this sounds like a job you rather not attempt, or you just need a little help along the way call A.J. Perri we’re always glad to help.
A.J. Perri is your New Jersey home comfort expert with specialists in heating, air conditioning, air quality and plumbing.