Knowing when to replace your furnace gas valve is a vital part of keeping your home comfortable, protected and cost-effective. The gas valve is an often overlooked part of your heating system—but without it, your furnace can’t function.

In this blog, May's Heating & Air will share the key signs of a malfunctioning gas valve. Whether you’re troubleshooting a potential problem or thinking proactively, this guide for Frederick, Maryland, homeowners will help you recognize the need for furnace gas valve replacement—and how to reach out to the trusted team at May's Heating & Air.

What is a Furnace Gas Valve and Why is It Important?

To begin, it's important to know what a furnace gas valve is and what it controls. The furnace gas valve regulates the flow of natural gas or propane into the unit's burner assembly, providing the fuel necessary for the combustion process to occur and produce heat. If gas flow is blocked, a gas-powered furnace won't give off any heat.

Also an important safety feature, the furnace gas valve is designed to cut off gas flow in the event of a mechanical issue—preventing a potentially dangerous gas leak. A typical furnace gas valve lifespan is about 10 to 20 years on average. While replacement price can change based on the model of furnace and if any additional repairs are needed, replacing a furnace gas valve costs an average of $300 to $800.

Furnace Not Igniting

One of the indications you may need to replace your furnace gas valve is if the furnace is not igniting or if the pilot light won't light. Gas is the energy source for combustion. Without proper gas flow through the system, a furnace won’t start up. Sometimes, homeowners also report that the igniter clicks but there's no flame.

However, a furnace not igniting or a pilot light that won't light or stay lit also could be signs of  other mechanical breakdowns, such as a damaged sensor, an issue with the thermocouple or insufficient fuel supply. If you notice these signs, it's important to call a certified HVAC technician for an inspection. They'll professionally diagnose whether the problem a thermocouple vs gas valve issue, or if there's another reason your furnace won't start or the pilot light won't stay lit.

Gas Smell Coming from Furnace

One serious sign of a malfunctioning furnace gas valve is a strong odor of gas coming from your furnace. This isn’t just a furnace maintenance issue—it’s an urgent safety risk. A gas leak can create a fire, explosion or even carbon monoxide poisoning. If you smell gas, evacuate the home immediately, call your gas company or 911, and then reach out to May's Heating & Air for emergency furnace repair.

Furnace is Short Cycling

Faulty gas valve symptoms also include short cycling. Short cycling describes when a furnace starts, but then quickly stops instead of running a full cycle. This might be occurring because a faulty furnace gas valve can result in inconsistent gas flow. A valve malfunction also could cause your furnace to power off to prevent creating a gas leak.

At the same time, sometimes furnace short cycling is the result of different underlying issues, so it's important to call a qualified heating expert for evaluation and possible furnace repair. 

What to Do If You Think Your Furnace Gas Valve Isn't Working?

If you believe your furnace gas valve is broken, it’s important to act quickly and safely.

First, shut off the gas supply to prevent any further risk, then turn off your furnace. Don’t try to repair the valve yourself. DIY gas valve repair can result in dangerous situations if done incorrectly and also could void your warranty and gas valve coverage. Whether the gas valve is stuck open, closed or has some other issue—gas valve work isn’t a task for someone without specialized tools and training. Plus, when it comes to weighing gas valve repair and gas valve replacement, it's almost always recommended to replace a gas valve instead of repairing it. 

Call May's Heating & Air to Be Sure Your Furnace is Ready for the Frederick, Maryland, Chill

To replace your furnace gas valve safely, contact the professional Frederick, Maryland, HVAC company—May's Heating & Air. Our trained technicians know exactly what to do when it comes to gas valve troubleshooting. We'll pinpoint what's wrong, perform the gas valve replacement safely and make sure your furnace is running at peak performance. To save even more power, we can even pair your system with one of our smart thermostats or provide furnace installation service to help you replace your outdated heating system.

Don’t delay critical repairs. Call 301-834-1468 today for gas valve replacement services from May's Heating & Air.