When to Change Your AC Filters (and Other Maintenance Considerations)

dirty air conditioner filterMany people change their air filters before the start of the warm season when the air conditioning unit is expected to work the most. However, homeowners, particularly in sunny states like Florida, will use the AC all year, whether they remember to change the filter or not thinking something like “hey, if it ain’t broke, don’t fix it.” But it turns out that even a careless renter would be setting themselves up for some Summer heartbreak.

So what are AC filters and why do we need to change them so often?

Every AC unit has a set of air filters installed, but sometimes we don’t think about the why. We like to think that air filters simply clean the air in the room, remove allergens, dust, and various bacteria. As a matter of fact, while the filter does clean the air and remove allergens, its primary role is to maintain the air flow to the HVAC system. Simply put, the filter’s main job is to prevent the unit from clogging itself up, keeping it running, and keeping it from running up your power bill. Essentially, an air filter acts as a self-cleaning protection device for the AC unit, protecting the evaporator coil, the blower motor, and fan from getting dirty.

Replacing the AC filters routinely will keep the unit running smoothly, reduce costs, and help your health by preventing the buildup of mold and other allergens. While the primary reason is the health of your heating and cooling systems, always having a clean air filter will also improve the health of everyone in the home. Even if you are already healthy, having the air constantly cleaned up is essential for good health. For asthma patients or allergic people, changing the air filters routinely is all-the-more critical. Changing the air filters stops the spread and growth of molds, bacteria, and other allergens in the system’s interior components, and prevents them from being recirculated by the air conditioner.

How often should you change the air filters?

Most HVAC experts agree that AC air filters should be changed at least every three months for most homes. Of course, the frequency can be much higher if there are more occupants inside the home or if there are pets in the home — in that case, you may want to change the filter once every month or two.

Another thing to take into account is the pollution in the area. If you live in a densely built urban area, you should replace the air filters more frequently. The same goes if you live in a humid or forested area.

If you’re reading this and already feel the need to check your filter, there’s no time like the present. If you notice that the filter has a gray, damp look, you’re already well-behind schedule and it’s time for a new one.

More care and maintenance for AC units…

Changing the air filter should always be on your regular maintenance list, but there are other things you can do for the health of your AC (and your own!) For example, you should inspect the evaporator and the condenser coils for dirt and mold buildup. You should check the coils at least once a year because they can collect dirt, dust, and other allergens. Checking the coil fins is another thing you should do. These fins are particularly frail and can be easily bent, so make sure they are straight and clean. You can use a soft cloth or a comb to make sure to clean any dirt or dust that may have accumulated, but don’t try to scrub forcefully if you find this isn’t enough.

If routine maintenance doesn’t do the trick, and you find yourself with a gunked up AC that leaks or doesn’t blow cold, it’s time to call in a professional HVAC technician like Bob Heinmiller in Florida.