Knowing when to replace your furnace gas valve is an essential part of keeping your home safe, cozy and energy smart. The gas valve is an often ignored part of your heating system—but without it, your furnace won’t run properly.

In this blog, Diedrick's Heating and Air Conditioning will break down the key signs of a broken gas valve. Whether you’re trying to diagnose a suspected problem or just want more information about how a furnace works, this guide for Seymour, Wisconsin, homeowners will help you recognize the need for furnace gas valve replacement—and when to contact the professionals at Diedrick's Heating and Air Conditioning.

What is a Furnace Gas Valve and What Does It Do?

To begin, it's important to understand what a furnace gas valve is and what it is responsible for. The furnace gas valve controls the flow of natural gas or propane into the unit's burner assembly, allowing the combustion process to occur and generate heat. If gas isn't flowing, a gas-powered furnace won't give off any heat.

Also a key safety feature, the furnace gas valve is engineered to close automatically when an issue arises—preventing a potentially deadly gas leak. A typical furnace gas valve lifespan is about 10–20 years. While replacement price can change based on the kind of furnace and whether any other service is required, replacing a furnace gas valve costs an average of roughly $300–800.

The Furnace Won't Light

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 what fuels the burner. Without adequate gas flow through the system, a furnace can't ignite. Sometimes, homeowners also notice 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 issues, such as a bad flame sensor, an issue with the thermocouple or a pressure drop in the gas line. If you notice these signs, it's important to contact 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 light.

Gas Smell Coming from Furnace

One serious sign of a broken furnace gas valve is a gas smell coming from your furnace. This isn’t just a furnace maintenance issue—it’s an potentially deadly hazard. A gas leak can create a fire, explosion or even CO poisoning. If you smell gas, leave the home right away, call your gas company or 911, and then phone Diedrick's Heating and Air Conditioning for emergency furnace repair.

Your Furnace Keeps Starting and Stopping

Faulty gas valve symptoms also include short cycling. Short cycling is when a furnace starts, but then quickly stops instead of going through its full cycle. This might be occurring because a faulty furnace gas valve can produce inconsistent gas flow. A valve failure also could trigger your furnace to shut down to avoid creating a gas leak.

However, sometimes furnace short cycling is caused by other mechanical issues, so it's important to seek out a qualified heating expert for evaluation and possible furnace repair. 

What to Do When Your Furnace Gas Valve Isn't Working?

If you believe your furnace gas valve isn’t working properly, it’s critical to take the situation seriously.

First, cut off the gas supply to prevent any further risk, then cut power to your furnace. Don’t try to fix the valve on your own. DIY gas valve repair can create a deadly gas leak if not done right and also has the potential to void your warranty and gas valve coverage. Whether the gas valve is stuck open, closed or isn't working for another reason—gas valve work isn’t a task for someone without specialized tools and training. In addition, when it comes to comparing options between gas valve repair and gas valve replacement, it's almost always recommended to replace a gas valve instead of fixing it. 

Call Diedrick's Heating and Air Conditioning to Make Sure Your Furnace is Ready for the Seymour, Wisconsin, Cold

To replace your furnace gas valve safely, contact the professional Seymour, Wisconsin, HVAC company—Diedrick's Heating and Air Conditioning. Our HVAC experts know just what to do when it comes to gas valve troubleshooting. We'll identify the problem, handle the gas valve replacement safely and make sure your system is running at peak performance. To save even more power, we can even match your system with one of our smart thermostats or connect you with furnace installation service to help you replace your old, unsafe furnace.

Don’t delay critical repairs. Call 920-833-7967 today for gas valve replacement services from Diedrick's Heating and Air Conditioning.