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

It’s not unusual for heating systems to have a glitch every now and then. It could be as simple as a bad thermostat or an electrical problem. If your gas furnace won’t shut off, here are a few steps you can take to get a correctly working furnace again. 

Check the Air Filter 

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 satisfy your ideal temperature. 

This multiplies wear and tear on your furnace, as well as the likelihood of a malfunction and early failure. 

It can also make your furnace overheat and shut down for a time to cool down. 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 uncomfortable. 

We encourage replacing flat filters each 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 dusty and you should get a new one. 

If the matter was connected to a clogged air filter, putting in a fresh filter should fix this common problem when your heat won’t turn off. If not, we suggest checking your thermostat settings next. 

Check Out the Thermostat 

Your thermostat runs 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 adjusting an incorrect thermostat setting. 

Ensure Your Thermostat is Set to “Auto”.

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

“Auto” means the furnace blower will only run 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 increase wear and tear on your furnace. 

If your thermostat is switched to “on,” it will seem like your furnace is not turning off, but it’s really just the furnace blower you’re noticing. Switching it to “auto” should resolve the problem. It will also help you save money on your energy costs. 

Confirm Your Temperature Setting 

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 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 large temperature difference between the cold air outside and the warm indoors. 

As a test, you can try lowering the thermostat to correspond with the room. Then, wait a few minutes. This should make the furnace turn off momentarily. 

Put in New Batteries 

If you have a programmable thermostat, it’s probably battery powered. You can try replacing the 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 switch it to “off,” you will need to turn off the power. 

Turn Off 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 dedicated power switch. 

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

2. Next, look for the dedicated power switch to your heating system. It’s similar to a light switch and can be found on or near your furnace. Move the switch down to shut off power. 

3. Your furnace should be turned off now. 

If you had to switch off your system at the breaker, call 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 instances, you might need a professional when your heater won’t shut off. 

Fan Limit Switch Needs Replacing 

The furnace fan limit switch controls your furnace’s blower motor. If the switch goes out, it might sound like your furnace running nonstop, even though just the blower is going. 

You might see a furnace error code if there’s a problem with the limit switch. Your furnace will communicate through a flashing red light on the front of your heating system. 

Our Experts can identify and correct any issues 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. 

Defective Thermostat 

Like anything else in your home, your thermostat can wear out as time passes and need to be replaced. If it’s time for a new one, ask us about getting a smart thermostat. 

These thermostats make it easy to save energy, since they create an energy-efficient heating and cooling schedule based on your preferences. Additionally, 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 distribute hot air to vents throughout your home. If your home or ductwork is older, your furnace might be operating constantly because the ductwork is leaking hot air in the attic. 

Identifying this leaky ductwork and other airflow issues can be difficult to resolve on your own, since it’s concealed behind walls and ceilings. Our Experts can help with identifying 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 affects your comfort, energy efficiency and heating bill. When it involves furnaces, there’s a reason why we say we’re Experts in our industry. You can rely 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 954-736-4314 to book your appointment now.