The air filter is an essential part of your air conditioning system. Its primary purpose is to trap dust, lint, hair, and debris to help keep the AC blower and evaporator coil clean and ensure that the system continues cooling effectively. If you use a higher-rated, more efficient filter, it will also filter out some allergens and pollutants and thus help improve your home’s indoor air quality.

Replacing the air filter is by far the most essential AC maintenance task. If not done regularly, the filter will quickly get so dirty that it clogs up to where very little air can flow through it. The general recommendation is that you need to replace your AC filter at least every one to three months. Replacing the filter every two or three months is usually sufficient if your AC doesn’t run all that much.

If you’re running your air conditioning for hours every day, you’re probably best to replace the filter every four to six weeks instead. You should also replace the air filter more frequently if your home is overly dusty or you have indoor pets since both of these factors will cause it to get dirty and clog up more quickly. To understand why replacing the air filter regularly is so essential, here is a quick overview of some of the effects that it has on your AC system.

Improved Airflow and Faster Cooling

Air filters can quickly become clogged and lead to a major reduction in airflow. Any time the filter is too dirty, the blower will struggle greatly to draw air through the filter and into the air handler where the AC evaporator coil is located. The more the blower struggles and the less warm air there is coming into the system, the less cold air will blow out of your vents.

Central air conditioning works by pulling warm air from the building in through the return vents and ductwork and then forcing this air over the evaporator coil. As the warm air moves over the coil, much of the heat energy flows out of the air into the cold refrigerant within the coil.

If there is very little warm air coming in, the system will cool far more slowly and your AC may never be able to keep your home at the desired temperature. By replacing your air filter regularly, you can ensure that your air conditioning has sufficient airflow and cools much more quickly and more effectively.

Reduced Strain on AC Blower and Condenser

A dirty air filter also puts lots of additional strain on the entire AC system. When the blower struggles due to a dirty filter, it will start working harder and could overheat and suffer serious damage. The fact that the system will cool more slowly and thus need to run for longer times also puts additional strain on the outdoor AC condenser unit.

This increases the wear and tear on the unit and can lead to it breaking down and then needing to be repaired or even potentially replaced. This increased strain on the system is yet another reason why it’s essential that you replace the AC filter regularly.

Decreased Energy Costs

Replacing the air filter can also help to keep your energy bills from skyrocketing. The longer the system has to run and the harder it has to work, the more energy it will use. Except for on extremely hot days, your AC should normally never run for more than 20 to 30 minutes at a time. If it runs for longer than this or starts running almost continuously, you can be fairly certain that your electricity bill will be quite a bit higher next month.

Lower Chance of AC System Freezing

The AC evaporator coil can freeze for a few different reasons, such as when the coil is dirty or if the system is low on refrigerant. That being said, the most common reason an AC system will freeze is because there isn’t enough warm air coming in either due to a dirty filter or a blower that isn’t working effectively. When there isn’t sufficient warm air flowing over the evaporator coil, the refrigerant will remain much colder since it isn’t absorbing much heat. This can lead to the temperature of the evaporator coil staying cold enough that all of the condensation that forms on it will start to freeze.

Having your AC freeze up is a serious issue. Any time the coil freezes, the system will stop cooling and begin pumping warm air out of your vents when the coil is frozen. Still, the bigger issue is that you run a major risk of the compressor motor in the outdoor unit burning out or seizing up if you continue to let it run when the coil is frozen. Changing your air filter can greatly reduce the risk of all of these issues since it will help to ensure that there is adequate air flowing through the system.

At Polar Express Plumbing, Heating and Air Conditioning, we offer professional AC maintenance and repair services and our team is always here to help if you have any AC issues. We can also help if you need a new AC unit installed or any heating or indoor air quality services in the Lake Elsinore area. Give us a call today if you need to schedule a service call or if you have any questions.

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Anthony Dieringer
Anthony Dieringer

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