A sticking gas valve is more than just frustrating; it’s a safety hazard. Gas furnaces burn natural gas. They use an electric or flame-based ignition system to ignite natural gas as it’s released. If your furnace has a gas valve that’s sticking, though, it may not release or any natural gas, or it may continue to release natural gas nonstop.

How the Gas Valves Work on a Furnace

Most gas furnaces have one or two valves. You can find them on the side of your gas furnace. They work by controlling the release of natural gas.

Gas furnaces that have two gas valves will have a primary valve and a main valve. The primary valve releases natural gas to the pilot light, whereas the main valve releases natural gas to the burner. Regardless, all gas valves can either release natural gas, or they can prevent natural gas from being released.

Closed vs Open Sticking

What does it mean for a gas valve to “stick” exactly? Sticking refers to a phenomenon in which a gas valve – or any valve for that matter – remains stuck in a particular position. Gas valves have an open position, and they have a closed position. They are designed to toggle between these two positions while subsequently controlling the release of natural gas.

A gas valve that’s stuck closed won’t release natural gas. A gas valve that’s stuck open, on the other hand, will constantly release natural gas.

Turn Off Natural Gas to Home

If your furnace’s gas valve is stuck open, you should turn off the natural gas to your home. A gas valve that’s stuck closed will typically only affect your furnace’s operations. Your furnace won’t receive the natural gas it needs to create combustion and, thus, produce warm air. But a gas valve that’s stuck open will continue to release natural gas.

Furnaces are designed with safeguards to prevent them from leaking natural gas into homes. Gas valves, however, can still fail by sticking closed or open. If you believe your furnace has a gas valve that’s stuck open, you should turn off the natural gas to your home and seek professional assistance immediately.

In Conclusion

Sticking is somewhat rare with gas valves, but it can still occur. Gas valves can stick closed so that they fail to release natural gas, or they can stick open so that they always release natural gas. A professional heating, ventilation and cooling (HVAC) technician can help to diagnose and fix your stuck gas valve.