Why Does My Heating System Keep Turning Off?

November 12, 2019

Your heating system was working just fine at the end of last year’s heating season. Now, it just keeps turning on and off. What happened?

Is There Debris in the Flue?

Over the summer, leaves and other debris could have fallen into the heating system’s exhaust pipe. Animals may have thought it was a good place to build a nest.

Debris in the flue will cause the hot gases produced to bank back down into the furnace. The added hot gases can cause the inside of the furnace to overheat. A heat sensor on the furnace checking for this condition will turn the furnace off until it cools back down. Make sure your flue is clear of debris. This will allow an unobstructed path for the hot gases to escape.

Safety Sensors Starting to Fail

Your furnace has a variety of safety sensors that will shut it off if an unsafe condition starts to develop. One is mentioned above, where the inside of your furnace starts to reach an unsafe temperature.

Another sensor is making sure a flame is present while fuel is being fed to the combustion chamber. If a flame is not present, then an explosive atmosphere will quickly develop.

A different sensor is checking the airflow throughout the furnace. An insufficient volume of airflow will allow the heat exchanger to overheat. This condition can damage the heat exchanger and cause it to fail.

As sensors start to fail, they will turn off your heating system at lower and lower parameters. The specialists at Southern Comfort Mechanical in Lewisville, TX, are trained to check and verify that these sensors are working properly.

Make Sure You Have Good Airflow Through Your Heating System

If you haven’t changed your air filter, now is a good time to check it out. Remove the filter and hold it up to the light. If you cannot see through it, it should be replaced. Check it every month or so during the heating season to ensure its usability.

Are any of your heat vents closed or obstructed? Closed vents, even in rooms that are not being used, will not save on your heating bill. Too many closed vents will inhibit airflow through your heating system and may trip a safety sensor. Make sure they are open and not blocked. If you see dust flying out of them when the heat comes on, you may want to remove the vent covers and vacuum out the vents.

The trained and skilled heating technicians at Southern Comfort Mechanical are ready to assist you with any of your heating issues or repairs this winter. Your comfort is our concern. Call on us to help you with your preventive heating, cooling and indoor air quality needs.

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