6 Reasons Your Pilot Light Won't Stay Lit

If your furnace’s pilot light won’t stay lit, you may need a heating repair contractor. We’ll look at the reasons the pilot light can keep going out. It’s not a problem you can ignore. Without a pilot flame, your furnace can’t provide heat and may be unsafe to operate.

When you find the pilot light has gone out, it takes just a little time out of your schedule to reset it. If the issue keeps recurring, it’s not only annoying. It can mean there’s a bigger problem other than not having comfortable heat in your home. Here are six reasons the pilot light in your furnace won’t stay lit.

1. The Thermocouple Isn’t Working

Your furnace has a thermocouple that detects when the flame is lit. If it doesn’t detect a lit pilot light, it will turn off the gas valve and your furnace won’t work. The primary reasons the thermocouple can malfunction include the following:

• Dirty: If the pilot light won’t stay lit despite your efforts, check whether the thermocouple is dirty. After all, it’s always exposed to a hot flame, so it can get covered in soot. Fortunately, the thermocouple can be cleaned. First, turn off the furnace and wait for things to cool down. Remove the thermocouple and clean it with a wire brush, fine-grain sandpaper, or other coarse material; then reinstall it.
• Bent: If the thermocouple is bent, it may not line up, so the flame envelops the top of the rod. The unit then won’t read the flame. To fix the problem, shut off the gas and, once the system is cool, try to bend the part back into place.
• Broken: You’ve tried cleaning or realigning the thermocouple rod, or the part looks broken or burnt out. A failed thermocouple must be replaced. This is an inexpensive fix, but you’ll need a trusted professional to install the part correctly.

2. A Dirty Pilot Opening

If the pilot light is weak when you try to light it, the pilot orifice may be dirty. Signs the opening may be clogged include an unstable, wavy flame. It may also appear yellow instead of blue. If the flame is too weak, it won’t completely cover the thermocouple. 

You can use a thin needle to try to extract a clog from the port, which should get the pilot working again. If you’re not comfortable doing this, call a professional, as thoroughly cleaning the pilot orifice requires disassembling it. We don’t recommend doing this without experience.

3. Not Enough Oxygen

A furnace in an enclosed area may quickly run out of combustible air. If there’s not enough oxygen, the pilot light won’t stay lit. Call a professional as this is due to more than a lack of oxygen. It can also cause carbon monoxide to build up in your home, which can be deadly. A technician must find a solution before the situation turns dangerous, which may require relocating the furnace.

4. The Gas Regulator Has Gone Bad

The pilot light won’t stay on if there’s not enough gas going into the system. Your furnace may not have a sufficient gas supply due to a faulty gas regulator, which is located in the natural gas meter outside your home. Therefore, you may notice issues with other gas-powered appliances. You’ll need to contact the local utility company to address this problem. 

5. Natural Gas Availability Is Fluctuating

If the flow of natural gas to your home isn’t consistent, the pilot light in your furnace can go out. It doesn’t require much of a change in natural gas availability. An issue with the utility is likely if your neighbors are also having natural gas issues. There’s nothing your local HVAC repair company can do. Contact your utility company to inform them of the problem or learn whether they’re working on resolving it.

6. The Pilot Light Is Blowing Out

The pilot light can be blown out by a strong draft. If it’s a windy day or night, re-lighting the pilot can be fruitless. Also, make sure all the intake registers in your home are open. If some of them are closed or blocked, a vacuum effect can occur, causing the pilot light to go out. Or, the furnace’s output duct may be leaking, causing air to blow into the pilot area. 

How Do I Re-Light the Furnace Pilot Light?

Review the user manual for your furnace model. It’ll show its inner workings in detail and may provide instructions on how to light the pilot. The general procedure should be as follows:

• Open the front panel to access the pilot light.
• Turn the gas valve to the “Off” position.
• Wait 5 minutes for the gas to dissipate.
• Hold the reset button while pressing the ignitor.
• Hold the button down for 20 to 30 seconds.
• Once the pilot light is re-lit, turn the valve to the “On” position.

How Many Times Should I Try to Re-Light It?

Assume there’s a problem after two failed attempts to re-light the pilot light. It’s okay to try again if it doesn’t turn on after your first effort. However, if attempting to re-light it again is unsuccessful, turn the system off and call an HVAC company. It may have a serious internal issue that may require replacing key components or replacing the entire unit. 

Should I Ever Turn the Pilot Light Off?

Turning off the pilot light in the summer can save a small amount of energy and money. There’s no need for the system to burn gas when you’re not using it.

Call QRC If Your Pilot Light Won’t Stay Lit

Our EPA-certified heating repair professionals are available 24/7 to address a problem with your pilot light or any other part of your furnace. They arrive in trucks stocked with tools and replacement parts. Therefore, any issue can be addressed quickly to restore your heat and safety. If you need a furnace or heater repair in your commercial or residential property in Winston-Salem, NC, call (336) 281-5144.