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 issue. If your gas furnace won't shut 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 problems for many homeowners and their HVAC system. Here's why. It restricts airflow, making your furnace work harder and run longer to meet your ideal temperature.
This multiplies wear and tear on your furnace, as well as the likelihood of a malfunction and premature failure.
It can also make your furnace get too hot and shut off for a time to cool off. 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 more quickly, it can increase 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 replace it.
If the matter was connected to a clogged air filter, putting in a clean filter should fix 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 runs your furnace and simply tells the unit when to turn on and off. It's often the problem when your furnace won't stop running.
Sometimes having the heat turn off is as simple as changing 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 operate when the furnace does.
“On” indicates the furnace blower will operate constantly. This constant air flow can help with heat circulation but will also drive up your power bill and lead to wear and tear on your furnace.
If your thermostat is set 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 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 running until it reaches 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 warm. This is due to a big temperature difference between the cold air outside and the warm indoors.
As a check, you can try reducing the thermostat to match the room. Then, wait a couple of minutes. This should make the furnace turn off in a few minutes.
Put in Fresh Batteries
If you have a programmable thermostat, it's likely battery powered. You can test putting in new batteries to see if that solves 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 cut the power.
Turn Off the Power
Thermostat seems to be working fine but your furnace still won't shut off? There are two spots you can cut the power to your heating unit: at the breaker box and at its specific power switch.
- Go to your breaker box and locate the breaker marked "furnace." Move the breaker switch to the right to shut off power.
- Next, look for the specific power switch to your heating system. It looks like a light switch and is located on or near your furnace. Move the switch down to shut off power.
- Your furnace should be turned off now.
If you had to switch off your system at the breaker, contact us at 204-800-0613 for professional service, as you may require furnace repair.
What Causes a Furnace to Keep Running?
Occasionally fixing this problem can be as easy as replacing your air filter or changing thermostat settings. In other instances, you might need a professional when your heater won't turn off.
Fan Limit Switch Needs Replacing
The furnace fan limit switch controls 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 an issue with the limit switch. Your furnace will communicate using a flashing red light on the front of your heating system.
Our Experts can diagnose and fix 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.
Like other things 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 needs. Plus, you'll be able to adjust and monitor your thermostat from just about anywhere with your phone.
Leaky Air Ducts
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 all the time because the ductwork is leaking hot air in the attic.
Diagnosing this leaky ductwork and other airflow problems can be challenging to troubleshoot 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 need.
Depend on Our Experts for All Your Furnace Repair Needs
Troubleshooting furnace problems can be annoying, especially 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 field. You can count 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 204-800-0613 to schedule your appointment now.