Gas Furnace Pilot Light Interruption: What Can Cause It

When the pilot light on your gas furnace won't stay lit, that leaves you with a furnace that won't run when you need it. If you're one of the many homeowners who doesn't know how to deal with an unpredictable pilot light, you're in the right place. Understanding the most common causes for pilot light issues can help you determine whether or not you need to call a furnace repair technician. Here's a look at some of the most common reasons why your furnace's pilot light keeps going out.

No Gas Supply

The most common reason for the pilot light on your furnace to go out is a lack of fuel. If the gas supply to your furnace has been interrupted, that will prevent the pilot light from burning. Check to be sure that the inbound gas valve on your home's gas line is open and that you're getting gas. You may need to call your gas supplier and ask them if there are any supply interruptions in the area. If you have ruled out the gas supply itself, it's time to consider the furnace.

Clogged Pilot Burner

If the burner for your pilot light is clogged, it may not be getting the fuel that's supposed to be flowing through the system. Over time, soot and other remnants of the fuel-burning process may clog the pilot light, or even contaminants in the gas supply can clog the ports. You may want to turn off the furnace and the gas supply, brush the pilot light area down, wipe it with a cloth, and then try again. If the ports were dirty, this will fix the problem. If the lines are clogged, though, you'll want to leave that to a furnace repair technician to address.

Malfunctioning Thermocouple Valve

The thermocouple on your pilot light system is intended to protect your home from gas leaks. The goal is for the thermocouple to sense whether or not your pilot light is burning and turn off the gas supply when it's not. However, if your thermocouple is faulty and it's not detecting the pilot light even though it's there, that will lead to a pilot light that can't stay burning because the thermocouple will turn off the gas. In this case, you'll want your furnace repair technician to replace the thermocouple with a new one to restore proper function.

These are a few of the most frequent issues that can cause a gas furnace pilot light to malfunction. If you're having trouble with your pilot light, reach out to a furnace repair technician near you.