Why Does My Furnace Keep Running?

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Why Does My Furnace Keep Running?

Anytime your furnace isn’t working correctly, there is cause for concern, but when an issue arises during the cold winter months, things can be even more serious. Unfortunately, many people don’t give their furnaces a second thought until there’s a problem. Preventive maintenance is always a good idea, so before the beginning of cold-weather season, give Pickerington Heating & Cooling a call and let one of our trained HVAC technicians perform a comprehensive inspection and cleaning to ensure that your HVAC system is in top condition and ready to take on whatever kind of weather winter throws at you. 

When your furnace comes on and turns off repeatedly, this is what is known as “short cycling,” meaning that it isn’t completing a full pre-determined and set cycle of operation for some reason. If your furnace is running continuously, there could be a number of reasons including.


Reasons Your Thermostat Won’t Stop Running

Your Thermostat’s Setting May Be Too High 

This is such a simple fix that it is easy to overlook. If the setting on your thermostat has been changed, this would explain why your furnace is running more than usual. Always check this first to rule out any other, more serious problems. Re-set your thermostat to its usual setting and it should begin running normally again. However, if it does not, then there is another issue causing your furnace to run so much. 

Your Furnace’s Air Filter Needs To Be Replaced 

When your furnace’s air filter becomes clogged with dirt, dust, and debris, air cannot flow freely through it. As a result, your furnace will run continuously in an attempt to heat your home the way it is designed to do. When the airflow to the furnace’s heat exchanger is limited by a clogged filter, the heat exchanger becomes overheated. When this happens, the furnace’s fan will run continuously. Your furnace will blow cold air into your home until the problem is resolved. 

This is an easy issue to fix (and easily preventable by simply replacing your filter prior to the onset of cold-weather season and as needed throughout the season), so if you are having problems with your furnace running nonstop, check the air filter. If it is dirty, replace it and see if this corrects the problem. Remember to check your furnace filter every 30 days during the months your system is in use and change it at least once during the season. 

Your Furnace Fan’s Setting Is In The ‘On’ Position 

On your thermostat, you will see a switch that has two settings: ‘Auto’ and ‘On’. This is the switch that controls your furnace’s fan. If this switch is set to the on position, your furnaces fan will run nonstop. Not only is this unnecessary, but it can also cause your system to become overworked and overheated, which in turn can result in damage to your HVAC system. Switch the setting to auto so that it will only run when it is needed to circulate warm air throughout your home. 

Issues With The Fan Limit Switch 

If your furnace’s fan limit switch has become faulty or damaged or if the wiring that controls it has become worn out, this will cause your furnace to run continuously. The fan limit switch is located beneath the hood of your furnace. It controls the activity of the blower inside your furnace. Inside the switch, there is a probe that activates the fan in the event that the burner assembly becomes overheated. Once the components are cooled down, it turns the fan off again. If this switch or the probe becomes damaged or defective, the furnace fan will run continuously. A professional HVAC technician will assess the situation to determine whether this is the problem and make any needed repairs right away. 

The Pilot Light Has Gone Out 

If your furnace is constantly running but the air coming through the vents into your home isn’t warm, the pilot light may have gone out. If this is the case, your furnace will run nonstop as it tries to heat your home. You can re-light the pilot flame yourself, or you can call us and one of our HVAC technicians will be happy to do it for you. 


Do You Still Need Help With Your Furnace?

If you are having problems with your furnace running continuously and you need help to find and fix the problem, give Pickerington Heating & Cooling a call at 614-837-4026 or visit us online at https://www.pickheat.com/appointments/. We can set you up with an appointment right away. One of our fully trained and licensed HVAC technicians will find the problem with your furnace and have it working again in no time. We’re here to meet all of your HVAC needs 24 hours a day, seven days a week, 365 days a year. The comfort and satisfaction of our customers is always our number one priority.