It's not unheard of for heating systems to have a problem once in a while. It could be as simple as a bad thermostat or an electrical issue. If your gas furnace won't turn off, here are a few steps you can take to get a correctly working furnace again.
Examine the Air Filter
A dirty air filter creates issues for many homeowners and their HVAC system. Here's why. It restricts airflow, making your furnace work harder and run longer to satisfy your ideal temperature.
This increases wear and tear 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 repeating 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 unpleasant.
We recommend replacing flat filters monthly 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 see light through your filter, it's too dirty and you should replace it.
If the matter was linked to a clogged air filter, putting in a fresh filter should solve this common problem when your heat won't turn off. If not, we recommend 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.
At times having the heat turn off is as easy 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 run when the furnace does.
“On” means the furnace blower will operate continuously. This constant air flow can help with heat circulation 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 seem like your furnace is not shutting off, but it's really just the furnace blower you're hearing. Switching it to "auto" should resolve the problem. It will also help you spend less 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 greater than the room air temp, your furnace will keep operating until it hits your desired temp.
Remember that if it's extremely cold outside, your furnace will have to run much longer than usual to keep your home cozy. This is because of a big temperature difference between the cold air outside and the warm indoors.
As a test, you can try decreasing the thermostat to correspond with the room. Then, wait a few minutes. This should make the furnace shut off in a few minutes.
Put in New Batteries
If you use a programmable thermostat, it's likely battery powered. You can try putting in new batteries to see if that resolves the problem. 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.
Cut the Power
Thermostat seems to be working fine but your furnace still won't shut off? There are two spots you can shut off the power to your heating unit: at the breaker box and at its dedicated power switch.
- Head to your breaker box and locate the breaker marked "furnace." Push the breaker switch to the right to cut power.
- Next, search for the dedicated power switch to your heating system. It's similar to a light switch and is located on or near your furnace. Move the switch down to cut power.
- Your furnace should be shut off now.
If you had to turn off your system at the breaker, contact us at 215-278-9690 for professional service, as you may need furnace repair.
What Causes a Furnace to Keep Running?
Sometimes correcting this problem can be as simple as replacing your air filter or adjusting thermostat settings. In other instances, you might want a professional when your heater won't shut off.
Fan Limit Switch Needs Replacing
The furnace fan limit switch regulates your furnace's blower motor. If the switch goes bad, it might seem like your furnace running continuously, even though just the blower is running.
You might notice a furnace error code if there's a problem with the limit switch. Your furnace will speak via a blinking red light on the front of your heating system.
Our Experts can diagnose and correct any problems you're having with your furnace blower motor. Often this can involve replacement parts, such as the control board, faulty wiring or the fan switch itself.
Like anything else in your home, your thermostat can wear out as time passes and need to be replaced. If you're due for a new one, ask us about installing a smart thermostat.
These thermostats make it easy to save energy, since they develop an energy-efficient heating and cooling schedule according to your preferences. Additionally, you'll be able to adjust 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 across your home. If your home or ductwork is older, your furnace might be running 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.
Depend on Our Experts for All Your Furnace Repair Needs
Troubleshooting furnace problems can be inconvenient, particularly when it affects your comfort, energy efficiency and heating bill. When it involves furnaces, there's a reason why we say we're Experts in our field. You can count on our ACE-certified technicians to resolve 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 215-278-9690 to schedule your appointment today.