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The Impact of Dirty Air Filters on Energy Consumption


An HVAC unit is one of the biggest electrical devices we use in our homes. HVAC units come in many shapes, sizes, and functionalities. But there is one common thing to all of them that plays a crucial role in their functions: air filters. A good air filter supplier will always agree that filters are a big part of all HVAC devices. But with use, air filters can get dirty. Dirty air filters can increase energy consumption without proper care and replacement, making your electricity bills rise.

Why Filters Get Dirty

Whether the HVAC unit in question is a furnace or an air conditioner, the main job of these machines is to balance the indoor temperature. But because of their closed rooms, these machines also must work in ventilating the space. The air filter inside an HVAC system filters the indoor air and traps undesirable elements such as pet dander, mold, dust, fiber, and other microbes. Because of this, whether the filter is a 21x22x1 air filters or a 14x30x1 air filters, it gets dirty easily and can also get clogged.

Impact of Dirty Air Filters on Energy Consumption

A lot of us do not want to worry about changing the air filters in the HVAC system. But even though the obvious side effect of dirty filters is the decrease in indoor air quality, there is another hidden consequence. The clogged air filter can be the cause of your increased electricity bills. But how does it happen? The process works like a chain of incidents:

Filter Gets Clogged

From constant use, the air always passes through the air filter in the machine. The more pollutants there are in the air, the more the filter is likely to get clogged. After around 2 to 3 months, the filter can accumulate enough dirt particles that get too densely clogged. The trapped dust particles damage the filter’s ability to function.

Trouble in Ventilation

When the filter gets so clogged that the air cannot find enough space to move through, that is when the trouble begins. Because of the accumulated particles, the density of the air filter increases, making the pathway more difficult for the air current to pass through.

Extra Effort Needed to Circulate Air

As the air cannot pass through the filter as easily as before, the machine has to exert more energy to make the airflow as required. The machine has to work extra hard to circulate the necessary amount of air, so it consumes more energy than normal. Often, it is seen that the strain that comes over the machine damages other parts of the machine as well.

High Energy Consumption

The clogged air filter strains the HVAC system so much that it causes higher energy consumption. And as we know, with higher energy consumption comes higher electricity bills. Even though you can ignore the rise in the bills, you should not leave the filter because the continued situation can cause major damage to the machine. If you are not careful, you might have to pay the full amount to buy another new system.


Even if it seems to be a made-up fact, the culprit behind the sudden rise of your electricity bills could indeed be the dirty AC air filters in your HVAC units. This part of the machine seems like a trivial thing, but it is one of the most important parts of the machine. To make sure that your HVAC unit works well and the indoor air is of the highest quality, you need to arrange for proper maintenance and replace the air filter, when necessary, from a reputed supplier like Simply Filters.


Jeff Campbell