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Bartels Heating & Cooling Blog

How a Clogged Filter Can Damage Your Furnace

man-with-filterThe most common nugget of wisdom we impart to our customers to help them help their furnaces is to regularly change the furnace filter. This filter is usually located on the HVAC cabinet at the point where the return air ducts connect to where the blower is located. The filter does the job of blocking debris coming through the return air ducts so it won’t enter the cabinet and contaminant the furnace, blower, and other parts of the HVAC system. This filter isn’t self-cleaning, and after one to three months the congestion in the filter will start to cause problems and even lead to damage to the furnace. 

We want you to have a healthy and reliable furnace. We’re always ready to assist with heating repair in Cincinnati, OH when you need it, but we know you’d much rather not have to call us in the first place. Regularly changing the furnace filter goes a long way toward preventing needless furnace problems. To help you better grasp why changing the filter is so important, we’ll list how a clogged filter can damage a furnace.

Strain on the blower 

The most immediate problem that a congested and dirty air filter creates is that it restricts airflow into the furnace. This places strain on the blower fan, which draws the air through the return ducts and the filter. The congested filter forces the blower fan to work much harder, and this often leads to the blower motor burning out. (You may receive a warning of this if the furnace starts to trip a circuit breaker; this is the motor overheating.) Replacing the blower motor is often an expensive repair to make. 

Overheated furnace

Lack of airflow creates another major problem for a gas furnace, which is that it causes the heat exchanger to fail to cool down. The heat exchanger is the part of a gas furnace that heats up from the combustion gas and then transfers the heat from its metal surface to the air pushed around it from the blower. When airflow declines, the exchanger will not cool down enough. As a safety precaution, the furnace has a limit switch to shut the system down, but an overheated furnace is a major problem and it can cause serious damage to the heat exchanger—another expensive part to replace. 

Dust and debris infiltration

Congestion and clogging can defeat the basic purpose of the filter, which is to stop debris from entering the HVAC cabinet. When a filter becomes fully clogged, it will start to distort from the extra air pressure placed on it. When this occurs, the distorted filter will begin permitting dust, lint, and other particles to slip around the filter’s edges. Dust contamination in a furnace interior can lead to major problems, such as rapidly burnt-out motors, failed electronic ignition systems, and burners that won’t light or won’t remain on for long. 

Severe damage to the blower

In extreme cases, the strain placed on a clogged filter can cause it to collapse and fall into the blower assembly, damaging the fan itself. 

Call Bartels Heating & Cooling “For a Comfortable Way of Life”! We have 24-hour emergency service available.

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