Many homeowners have heard about the importance of regular HVAC air filter changes already. But, this task tends to be placed on the back burner when it comes to home maintenance. Why? The main reason may be that the air filter is out of sight and out of mind until something goes wrong. Another possible cause is that the air filter change is too easy and the part is inexpensive and this lures people into thinking that this process is not important. We tend to value things that have a higher investment in terms of time and value. But, regular air filter changes are extremely important, and ignoring them can cost a lot of money.

Why Do We Need Air Filters?

HVAC air filters can improve the indoor air quality (IAQ) to a certain degree. But, they are not as effective in this role as HEPA filters, air purifiers, and other dedicated systems. A standard air filter can remove some contaminants, but the purpose is to keep that dirt and debris out of the HVAC system.

There are sensitive components and motors in the HVAC system that are prone to degraded performance and failure if they become grimy. An air filter is a mechanical filtration membrane that traps contaminants on the filter surface. It must be sized correctly, the size is printed on the filter rim, and it should match the number in the owner’s manual for your system.

7 Clogged Air Filter Consequences

There are a large number of airborne contaminants circulating through our homes. These pollutants will degrade the IAQ to varying degrees, but many of them will ultimately be captured by the air filter. During a day when the HVAC system is running, the indoor air will be circulated multiple times through the air filter. Let’s take a look at seven clogged air filter consequences in more detail:

1.   A Loss of Performance

The HVAC system needs to move the treated air (warm or cool) through the home to make the internal spaces feel comfortable. If the airflow is impeded by a clogged air filter, this will cause a noticeable loss of performance. You may place your hand on the air vent and notice an extremely low level of treated air that has a negligible effect on the home. If you have a larger or multilevel home, you may notice hot and cold spots because the lack of airflow makes the heating or cooling uneven and unreliable.

2.   A Loss of Energy Efficiency

The HVAC system has a blower motor that drives a fan that pushes the air through the air ducts and out of the vents. This key component uses a lot of energy, it works hard, and it needs to work even harder if it has to push the air through a clogged air filter. When components are overworked, they tend to consume more energy, and this really drives up the energy bills.

3.   Fan Motor Burn Out

The aforementioned overworked fan is more prone to overheating and burn out. This can lead to a total system failure and an unexpected repair bill. If this is a potential problem, you may smell a burning smell at the vents, or you may hear strange noises.

4.   A Cracked Heat Exchanger

During the winter months, a lack of airflow will prevent the dissipation of heat around the heat exchanger. In extreme cases, this may cause the heat exchanger to crack, and this is extremely dangerous for the entire home. The first risk is the release of poisonous carbon monoxide, which is known as the silent killer for good reason. The second risk is the surface cracks that can allow flames to escape the heat exchanger. This is the cause of many house fires every year, and the consequences are often fatal. A heat exchanger crack is hard to detect because the surface contracts when it’s closed, and the crack seals up. So, it’s important to keep the air filter clean and install a carbon monoxide detector to keep everyone in the home safe. If you suspect a problem with your heat exchanger, contact your local heating and cooling specialist to check it out for you.

5.   Frozen Evaporator Coils

When the air filter is clogged, dirt and dust will build up inside the equipment. Over time, the components will become dirty and grimy, and this will have a negative effect on the cooling coils. The evaporator coils may become coated with ice, and the frozen coils will reduce the capability of the HVAC system to keep the indoor temperature consistent. This will force the system to work harder, risking damage to the components and driving up the energy bills. Eventually, the system may fail, and an earlier than expected replacement may be required.

6.   Dirty Air Ducts

If the air filters are dirty, this will cause the air ducts to become dirty too. The airborne contaminants will go around the filter and accumulate on the inner surfaces of the ducts. This will lower the IAQ, and the dirt may back up into the HVAC system components, where they may cause damage.

7.   Ongoing Component Damage

A forced-air system is designed to handle a certain volume of air during each cycle. If the air filter is clogged, this will degrade the airflow, and the individual components will need to work much harder than intended. Operating outside engineering tolerances for too long will cause damage that may be irreversible. Over a typical heating or cooling season, this can be very noticeable, and the frequency of repairs may accelerate. Eventually, it will be impossible or untenable to make a repair, and an early replacement can be expensive.

In Conclusion

Checking the air filter is easy, access the filter housing (the full details are in the owner’s manual), take a look, and if it’s very dirty, put in a fresh one. All HVAC systems rely on a steady supply of air to work at optimal efficiency. Although air filter changes seem trivial, they should be treated as a priority because clogged filters can cause a lot of problems.

If you’re concerned about the performance and efficiency of your HVAC system, contact your local heating and cooling specialist today.