Knowing how gas furnace pilot light troubleshooting works can help when your heating system isn’t performing as expected. A lack of heat can be due to a faulty pilot light. The issue can’t be ignored; it’ll prevent your furnace from warming your Boise, ID, home and can be a safety hazard. We’ll now look at some pilot light troubleshooting steps and when to call one of our heating installation and repair professionals.

1. Know the Signs of a Faulty Pilot Light

The pilot light serves as an ignition source inside your furnace. It ignites the fuel that enters the combustion chamber so your furnace can heat the air that circulates in your home. Normally, the pilot light burns blue. Here are some of the top signs it needs attention:

  • Your furnace is not producing heat
  • The pilot light is weak or yellow
  • The pilot light is not staying lit
  • The pilot light is flickering
  • There’s a gas smell in your home
  • Adjustments won’t yield a solid flame
  • Your energy bills are higher

2. Check the Circuit Breaker

If the circuit breaker for your furnace has tripped, the unit won’t turn on. Resetting the breaker should restore power. However, if the power isn’t restored or the breaker trips repeatedly, call a professional instead of resetting it again. There may be faulty wiring or a safety issue with your furnace.

3. Inspect the Furnace Gas Supply

If your gas furnace pilot light isn’t lit, it may be due to a gas supply issue. Check that the gas valve is on. Here’s how to relight a pilot light if the gas valve is off. Make sure the valve is in the “Off” position and leave it that way for three minutes. Next, switch it to the “Pilot” setting. Light a match and hold it to the pilot opening while pushing the reset button; once the pilot flame is brightly lit, move the valve to the “On” position.

If this process makes you uneasy or the pilot light does not go on, contact a professional.

4. Check for Dirt and Clogs

Dirt and debris buildup in your furnace can interfere with the pilot light. It may be yellow, weak, or nonexistent. Cleaning the buildup inside the unit can restore normal performance. You can clean the area around the pilot with compressed air or a wire brush. However, the various parts of the pilot assembly are sensitive and are easily damaged. Therefore, it’s best to call a technician who has the tools and experience to safely clean your furnace.

5. Check the Thermocouple

A built-in safety device, the thermocouple detects whether the pilot light is lit; if not, it prevents the furnace from turning on. Based on the pilot’s status, it signals the gas valve to open or close. If the pilot light keeps going out, it’s often because of a faulty thermocouple. Normally, it turns off the gas if the flame is out. But if the thermocouple is covered in soot, displaced, broken, or malfunctioning, it may not sense the pilot light. Whether the thermocouple is dirty or damaged, have a professional handle it; it’s a delicate component.

6. Look for Drafts

If there’s a breeze or draft around your furnace, it can blow out the pilot light. A draft can be subtle and hard to find. Check the area around the unit, holding a lit candle or stick of incense. If it flickers or goes out, you’ve found the source of the draft. It can typically be resolved by sealing a hole, caulking around a window or door, or installing weatherstripping.

7. See Whether the Ignition System Is Working

Turn off the power to the furnace and remove the front panel. Locate the ignition components. If any parts appear damaged, loose, or corroded, have them replaced by a professional. Also, look for worn or frayed wires. Don’t try to repair or replace any parts yourself. Your efforts at gas furnace pilot light troubleshooting will help your heating contractor more quickly locate the problem and find a solution.

8. Replace the Air Filter

A clogged air filter can restrict airflow. The heat exchanger can then overheat, causing your furnace to shut down. One sign of this is that the gas furnace pilot light won’t light. Replacing the air filter is simple. If this is the only reason your furnace isn’t working, the issue should be completely resolved.

Call Express Plumbing Heating & Air

Known for reliable heating repair in Idaho, we have licensed, highly retained professionals with a deep understanding of the heating needs of local home and business owners. Prompt service ensures your safety when a potentially dangerous issue arises. Our technicians provide quick gas furnace pilot light troubleshooting and repair. They immediately determine the source of the issue, clean dirt and debris if necessary, and repair or replace valves, ignitors, thermostats, and any other malfunctioning components. Call Express Plumbing Heating & Air (208) 357-9251 to request service.

Brad Jordan

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