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 few steps you can take to get a correctly working furnace again.
A dirty air filter creates problems for numerous homeowners and their HVAC system. Here’s why. It restricts airflow, forcing your furnace to work harder and run longer to meet your ideal temperature.
This increases wear and tear on your furnace, as well as the likelihood of a breakdown and early failure.
It can also make your furnace get too hot and shut down for a time to cool off. Then it will keep duplicating this process when your furnace switches on. This is known as short cycling. In addition to wearing out your furnace more quickly, it can drive up your heating bill and make your home feel unpleasant.
We recommend replacing flat filters once a month and pleated filters every three months. If you can’t remember the last time you got a new furnace filter, pull it out 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 linked to a clogged air filter, replacing it with a clean filter should solve this common problem when your heat won’t turn off. If not, we recommend checking your thermostat settings next.
Your thermostat controls your furnace and basically tells 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 simple as changing a wrong thermostat setting.
Make Sure 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” indicates the furnace blower will run constantly. This constant air flow can help with heat distribution but will also increase your power bill and increase wear and tear on your furnace.
If your thermostat is set to “on,” it will sound like your furnace is not turning off, but it’s really just the furnace blower you’re hearing. Changing it to “auto” should resolve the problem. It will also help you spend less money on your energy costs.
If your thermostat won’t turn off heat, check the temperature setting to the room temperature. If it’s greater than the room air temp, your furnace will keep operating until it reaches your desired temp.
Remember that if it’s very cold outside, your furnace will have to operate much longer than usual to keep your home warm. This is because of a big temperature difference between the cold air outside and the warm indoors.
As a check, you can try lowering the setting to correspond with the room. Then, wait a couple of minutes. This should make the furnace turn off momentarily.
If you have a programmable thermostat, it’s likely battery powered. You can try putting in new batteries to see if that resolves the issue. If it doesn’t or if there’s wiring to your electrical system, shift it to “off.”
If your furnace won’t shut off after you switch it to “off,” you will need to cut the power.
Thermostat appears to be working fine but your furnace still won’t turn off? There are two spots you can cut the power to your heating unit: at the breaker box and at its specific power switch.
If you had to switch off your system at the breaker, call us at for professional service, as you may need furnace repair.
Sometimes fixing this problem can be as simple as changing your air filter or adjusting thermostat settings. In other instances, you might want a professional when your heater won’t turn off.
The furnace fan limit switch regulates your furnace’s blower motor. If the switch goes out, it might sound like your furnace running nonstop, even though just the blower is running.
You might see a furnace error code if there’s an issue with the limit switch. Your furnace will speak via a blinking red light on the front of your heating system.
Our Experts can identify and fix any issues you’re having with your furnace blower motor. Often this can involve replacement parts, like the control board, faulty wiring or the fan switch itself.
Like other things in your home, your thermostat can break down as time passes and need to be replaced. If it’s time for a new one, ask us about installing a smart thermostat.
These thermostats make it easy to save energy, because they create an energy-efficient heating and cooling schedule based on your needs. Additionally, you’ll be able to adjust and keep tabs on your thermostat from just about anywhere with your phone.
Your furnace relies on ductwork to distribute hot air to vents across your home. If your home or ductwork is older, your furnace might be operating all the time because the ductwork is leaking hot air in the attic.
Identifying this leaky ductwork and other airflow problems can be difficult to resolve on your own, since it’s hidden behind walls and ceilings. Our Experts can help with identifying and taking care of any air duct repair service that you need.
Troubleshooting furnace problems can be inconvenient, particularly when it impacts your comfort, energy efficiency and heating bill. When it comes to furnaces, there’s a reason why we say we’re Experts in our industry. You can depend on our ACE-certified technicians to solve your problem quickly and affordably. And what’s even better, we stand behind our HVAC system repairs with a 100% satisfaction guarantee for one year.* Call us at to book your appointment now.
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There’s no reason to skip your seasonal maintenance that saves energy and helps ensure your air conditioner and heater will work reliably all season long.
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