There are many possible causes for a gas furnace that’s not generating heat. Fortunately, you could try and address some of these causes yourself. Below are some of the most common causes and what you could do to resolve the issue.
Your Furnace Needs a Reset
Press the reset button of your furnace and wait to see if it starts generating heated air. If not, you would need to do more checks. Better yet, call a professional to find out if your unit requires adjustment, repair, or replacement.
Check if the thermostat’s temperature is set to trigger the furnace to produce heat. If yes, but your furnace still fails to function, check if your thermostat’s interior is clean. Check if the batteries are still working and if there are no faulty circuit breakers and fuses as well, advises a heating repair expert in Salt Lake City.
Filthy Furnace Filters
If your furnace filter is dirty, it could restrict airflow throughout your furnace and lead to overheating. Check if the filter is dirty and proceed to clean it if it is.
Closed Heating Registers
If you close many heating registers, this could lead to heat building up inside your furnace. This, in turn, would force air out of the duct leaks and make blowers work overtime to accommodate the extra pressure. HVAC specialists recommend keeping 80% of heating registers open, so air won’t build up inside.
Grimy Flame Sensors
Flame sensors protect your furnace from unstable burning fuel, so grimy flame sensors could cause the furnace to malfunction. If you could detach the flame sensor from your furnace, do so and proceed to scrub away dust and debris buildup using sandpaper, emery cloth, or even an abrasive sponge.
Your Pilot Light isn’t Turned On
First, check if the pilot light is truly turned off. Turn off the gas valve and wait for at least five minutes. If your furnace has a reset button, turn the gas valve to the position of the pilot and put a flame to the opening as you push down the button for at least 30 seconds. If it’s still not lighting, do the same thing after several minutes. This time, hold the button for 40 to 60 seconds. If you manage to turn on the pilot, but it fails to stay lit, there might be an issue with the ignition or thermocouple system.
If — after addressing the issues above — you’re still experiencing problems with your gas furnace, it’s best to contact a repair specialist ASAP. Refrain from tinkering with your gas furnace until help arrives to avoid more problems.