What to Do When Your Heater Won’t Turn Off!

It’s not unusual for heating systems to have a problem once in a while. It could be as straightforward as a broken thermostat or an electrical issue. If your gas furnace won’t shut off, here are a few steps you can take to get a properly working furnace again. 

Examine the Air Filter 

A dirty air filter causes problems for numerous homeowners and their HVAC system. Here’s why. It limits airflow, making your furnace work harder and run longer to satisfy your desired temperature. 

This increases usage on your furnace, as well as the likelihood of a malfunction and premature failure. 

It can also make your furnace overheat and shut down 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 drive up your heating bill and make your home feel unpleasant. 

We encourage replacing flat filters once a month and pleated filters every three months. If you can’t remember the last time you replaced your 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 replace it. 

If the matter was connected to a clogged air filter, replacing it with 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 the Thermostat 

Your thermostat controls your furnace and basically informs the unit when to turn on and off. It’s usually the problem when your furnace won’t stop running. 

At times having the heat turn off is as easy as changing an incorrect thermostat setting. 

Ensure Your Thermostat is Set to “Auto”.

Your thermostat has two settings, “auto” and “on,” that manage your heating system’s blower motor. 

“Auto” means the furnace blower will only operate when the furnace does. 

“On” indicates the furnace blower will operate constantly. This constant air flow can help with heat distribution but will also drive up your power bill and increase wear and tear on your furnace. 

If your thermostat is switched 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. 

Confirm Your Temperature Setting 

If your thermostat won’t turn off heat, compare 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 normal to keep your home cozy. This is due to a big temperature difference between the cold air outside and the warm indoors. 

As a test, you can try decreasing the temperature to match the room. Then, wait a few minutes. This should make the furnace turn off in a few minutes. 

Put in New Batteries 

If you have 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 shut off after you switch it to “off,” you will need to cut the power. 

Turn Off the Power 

Thermostat seems to be working fine but your furnace still won’t shut off? There are two places you can cut the power to your heating unit: at the breaker box and at its specific power switch. 

1. Go to your breaker box and locate the breaker labeled “furnace.” Push the breaker switch to the right to shut off power. 

2. Next, search for the specific power switch to your heating system. It looks like a light switch and is located on or near your furnace. Push the switch down to shut off power. 

3. Your furnace should be shut off now. 

If you had to turn off your system at the breaker, contact us at 954-736-4314 for professional service, as you may require furnace repair. 

What Causes a Furnace to Keep Running? 

Sometimes correcting this problem can be as easy as changing your air filter or adjusting thermostat settings. In other situations, you might need 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 see a furnace error code if there’s a problem with the limit switch. Your furnace will speak through a flashing red light on the front of your heating system. 

Our Experts can identify and correct any problems 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. 

Faulty Thermostat 

Like anything else in your home, your thermostat can wear out over time and need to be replaced. If you’re due for a new one, ask us about installing a smart thermostat. 

These thermostats make it simple to save energy, since they create an energy-efficient heating and cooling schedule according to your preferences. Plus, you’ll be able to set and monitor your thermostat from just about anywhere with your phone. 

Air Ducts Are Leaking 

Your furnace relies on ductwork to circulate hot air to vents throughout your home. If your home or ductwork is older, your furnace might be operating constantly since the ductwork is leaking hot air in the attic. 

Diagnosing this leaky ductwork and other airflow issues can be difficult to troubleshoot on your own, since it’s hidden behind walls and ceilings. Our Experts can help with diagnosing and taking care of any air duct repair service that you require. 

Rely on Our Experts for All Your Furnace Repair Needs 

Troubleshooting furnace problems can be inconvenient, particularly when it impacts 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 rely 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.* Contact us at 954-736-4314 to schedule your appointment now.