Why Does Your Pilot Light Keep Going Out?

Posted on: 20 October 2020

Homes that use gas to power their furnace are relatively common, but if your home has a standing pilot light, that means it's at least a decade old. Most modern furnaces use an electric ignition to light their furnace, precisely because a pilot light that keeps going out means that your furnace won't work.

But why does it keep going out? More importantly, what can you do to prevent it? There are a few reasons why your pilot light keeps malfunctioning, some of which are unavoidable and need to be fixed by a professional furnace repair technician.

It's Too Old

As mentioned above, pilot lights are slowly being replaced by electric ignitions, so if you have a pilot light in your furnace, it means that your furnace, and all the parts inside, are pretty old. Over time, these parts will begin to break down and malfunction, resulting in numerous furnace repair appointments. Instead of simply relighting the pilot light, it may be time to think about upgrading your system to a newer model.

Increased Airflow

The pilot light is tiny, so even the smallest draft inside your furnace can cause it to go out. Normally, the main culprit in this is a cracked heat exchanger, which regulates the air pressure inside the unit and minimizes airflow. The best way to fix this is to identify the source of the crack — such as the heat exchanger — and repair it, but that could be expensive depending on where the crack is.

Low Fuel Source

Even though most homes have their furnace hooked up to a city gas line, the gas valve that supplies the energy could be broken or dirty in some way. This creates a restricted flow of gas to the furnace, and in turn, the pilot light. A furnace repair service call to handle this is quick and relatively inexpensive, so contact your local HVAC company to get it taken care of as soon as possible to get your unit up and running.

Faulty Thermocouple

The thermocouple is a tiny rod that sits directly above the pilot light. It's only real job is to prevent gas from seeping into the home if the pilot light goes out, so if it's not working, it'll shut off all the gas to your home instantaneously. The only way to fix this is to replace the thermocouple, which should always be done by a trained furnace repair technician.

For more information, contact a furnace repair service in your area.