How to Test a Furnace Gas Valve

If the furnace is running and stops mid-cycle, check if it’s warm.

With winter fast approaching, the last thing a home needs is a broken furnace. Seasonal inspections and maintenance are always a worthwhile investment to ensure the home has a fully functional and reliable heat source for the coming cold weather.

One of the most common problems is a faulty gas valve. There are a few steps that can be taken to test the valve. While it’s always preferred to let a professional perform any repairs, especially to a gas furnace, the initial test can be done independently. If the problem is the gas supply to the home, contact the local gas provider. If the furnace components are the problem, contact a professional HVAC company for repairs.

Check the gas supply

When testing the furnace gas valve, begin by noting whether or not gas is entering the home by checking if the pilot light on the gas water heater is on, if the hot water spigot is producing hot water, if the burners are working on the gas stove, and if the gas fireplace starts. If it’s not a gas supply issue, continue with the following steps.

Check the furnace

If the furnace is running and stops mid-cycle, check if it’s warm. If so, it may not be a gas valve issue but the thermocouple. In this case, contact a professional for assistance.

If the furnace is cold, hold a voltmeter next to the igniter wire to see if it registers. If not, it may be an electrical issue. Anytime there’s an electrical issue with the HVAC system, it’s best to contact an expert for help, as these experienced and certified technicians can diagnose and repair the furnace.

The gas valve is likely faulty if the voltmeter registers and the igniter receives power. In this case, little can be done independently to help the situation. Instead, contact a certified HVAC repair company.

Knowing how to test a furnace gas valve is helpful, but attempting to replace it is not recommended as a DIY project, as it’s a dangerous task for the average homeowner. Instead, contact a reliable technician who can perform the task safely and efficiently.

Forecast Heating, Cooling, and Refrigeration serves residential and commercial customers in Summerlin, Anthem, North Las Vegas, Boulder City and Las Vegas. Call us at 702-919-4546.