It's not unheard of for heating systems to have a problem every now and then. It could be as simple as a bad thermostat or an electrical problem. If your gas furnace won't turn off, here are a couple steps you can take to get a properly working furnace again.
Check the Air Filter
A dirty air filter causes issues for many homeowners and their HVAC system. Here's why. It restricts airflow, forcing your furnace to work harder and run longer to satisfy your ideal temperature.
This multiplies usage on your furnace, as well as the odds of a malfunction and premature failure.
It can also make your furnace get too hot and shut off for a time to cool down. Then it will keep duplicating this process when your furnace turns on. This is known as short cycling. In addition to wearing out your furnace faster, it can increase your heating bill and make your home feel uncomfortable.
We encourage replacing flat filters monthly and pleated filters every three months. If you can't remember the last time you replaced your furnace filter, remove it and hold it up to the light. If you can't detect light through your filter, it's too dirty and you should get a new one.
If the matter was connected to a clogged air filter, putting in a clean filter should fix this common issue when your heat won't turn off. If not, we suggest checking your thermostat settings next.
Check Out the Thermostat
Your thermostat controls your furnace and basically informs the unit when to turn on and off. It's often to blame when your furnace won't stop running.
Sometimes having the heat turn off is as easy as changing a wrong thermostat setting.
Ensure Your Thermostat is Set to “Auto”
Your thermostat includes two settings, “auto” and “on,” that control your heating system's blower motor.
“Auto” indicates the furnace blower will only operate when the furnace does.
“On” means the furnace blower will operate constantly. This constant air flow can help with heat distribution but will also increase your power bill and lead to wear and tear on your furnace.
If your thermostat is switched to "on," it will sound like your furnace is not shutting off, but it's really just the furnace blower you're noticing. Switching it to "auto" should solve the problem. It will also help you save money on your energy costs.
Check Your Temperature Setting
If your thermostat won't turn off heat, check the temperature setting to the area temperature. If it's higher than the room air temp, your furnace will keep operating until it hits your desired temp.
Keep in mind that if it's very cold outside, your furnace will have to run much longer than usual to keep your home warm. This is due to a big temperature difference between the cold air outside and the warm indoors.
As a test, you can try reducing the temperature to correspond with the room. Then, wait a few minutes. This should make the furnace turn off momentarily.
Put in New Batteries
If you use a programmable thermostat, it's probably battery powered. You can test putting in new batteries to see if that resolves the problem. If it doesn't or if there's wiring to your electrical system, switch it to "off."
If your furnace won't turn off after you move it to "off," you will need to turn off the power.
Turn Off the Power
Thermostat seems to be working fine but your furnace still won't turn off? There are two places you can shut off the power to your heating unit: at the breaker box and at its specific power switch.
- Head to your breaker box and locate the breaker labeled "furnace." Move the breaker switch to the right to cut power.
- Next, look for the specific power switch to your heating system. It looks like a light switch and can be found on or close to your furnace. Push the switch down to cut power.
- Your furnace should be turned off now.
If you had to switch off your system at the breaker, call us at 304-760-5088 for professional service, as you may require furnace repair.
What Causes a Furnace to Keep Running?
Sometimes fixing this problem can be as easy as changing your air filter or changing thermostat settings. In other situations, you might need a professional when your heater won't turn off.
Fan Limit Switch Needs to Be Replaced
The furnace fan limit switch regulates your furnace's blower motor. If the switch goes bad, it might sound like your furnace running nonstop, even though just the blower is going.
You might notice a furnace error code if there's an issue with the limit switch. Your furnace will speak via a flashing red light on the front of your heating system.
Our Experts can identify and fix any problems you're having with your furnace blower motor. Sometimes this can involve replacement parts, like the control board, faulty wiring or the fan switch itself.
Defective Thermostat
Like other things in your home, your thermostat can break down over time and need to be replaced. If it's time for a new one, ask us about installing a smart thermostat.
These thermostats make it simple to save energy, because they create an energy-efficient heating and cooling schedule according to your needs. Additionally, you'll be able to set and keep tabs on your thermostat from just about anyplace with your phone.
Leaky Air Ducts
Your furnace uses ductwork to distribute hot air to vents throughout your home. If your home or ductwork is older, your furnace might be running constantly because the ductwork is leaking hot air in the attic.
Identifying this leaky ductwork and other airflow problems can be tricky to resolve on your own, since it's concealed behind walls and ceilings. Our Experts can help with diagnosing and taking care of any air duct repair service that you require.
Depend on Our Experts for All Your Furnace Repair Needs
Troubleshooting furnace problems can be annoying, especially when it affects your comfort, energy efficiency and heating bill. When it comes to furnaces, there's a reason why we say we're Experts in our field. You can count on our ACE-certified technicians to solve your problem quickly and affordably. And what's even better, we back our HVAC system repairs with a 100% satisfaction guarantee for one year.* Call us at 304-760-5088 to schedule your appointment today.