Furnace Not Blowing Air? Your System’s Air Filter Is to Blame

Air filters help to improve the quality of air that a furnace dumps into a building. They do this by trapping any unwanted particles from the air. Unfortunately, this particle-trapping role usually exposes them to the risk of getting clogged. And when this happens, it usually leads to furnace complications.

One of the most common complications of having a clogged filter is the furnace being unable to blow warm air into a home. Here is what you should know about why you should check your air filters as soon as you notice this symptom.

Your furnace is not blowing air because air can't get into the system

To keep dust and debris out of the furnace, air filters are usually located at the point where air enters into the system. As a result, every ounce of air that enters and leaves the system has to go through the filters. Therefore, when dirt and debris block a filter's openings, they deny the furnace air with which to work with. And since there is no air coming into the system, the system won't have air to blow into your home, even when the furnace's blower is functioning.

Your furnace is not blowing air because your clogged filters are causing it to overheat

The heating process starts with the blower pushing cold air to the heat exchanger. This affords the air the opportunity to get warmed before being pushed through the duct system and into the home. It also has another effect: cooling the heat exchanger.

The clogging of a furnace's filters usually leads to restricted airflow within the system. It has the effect of limiting the amount of cold air that flows over the heat exchanger, something that leaves it vulnerable to overheating.

To prevent the damaging effects of overheating, such as heat-exchanger cracks, manufacturers usually fit the furnace with a fan limit switch. This switch is made up of a thermostat that monitors the temperature of the supply plenum. And when the thermostat detects that the temperature is abnormally high, it shuts off the furnace. As a result, your home ends up not receiving heated air.

To solve this problem, remove the air filter from the furnace and then dip it in a solution of water and vinegar. Use a rag to clean the filter and then leave it in the open. After the filter dries, screw it back. This should be enough to unclog your system's air filters and thus restore your furnace's ability to blow air into your home.

Talk to a heating repair service for professional help. 


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