How Often Should I Change My Home Air Conditioning Filter?

Many homeowners in the Longwood area have heard that they need to replace their HVAC system’s air conditioning filter on a monthly basis. However, it is easy for busy people to overlook this task, and some might find that they go several months before remembering to replace their AC filter. Others might regularly complete this task on time, but wonder if it’s truly necessary. There are a few things to consider when determining a more accurate air conditioning filter replacement schedule.

Factors That Affect How Often You Should Change Your Filter

Some of the most common factors that affect how often you should change your air filter are:

1. How many people live in your household?

An average sized family of 4 would have to replace their air conditioning filter more frequently than a single person.

2. How much do you use the system?

If it’s a full-time residence with more than a single occupant, it’s not recommended you go longer than 90 days without replacing your air conditioning filter.

If the residence is a vacation home where you don’t use the system as much, you could even change the filter every few months.

If you live in Florida and run your air conditioner all day every day, you would need to change it as frequently as every 30 days. You’ll want to check it at least every month to be sure it’s not dirty.

Dirty Air Conditioning Filter
Dirty AC Filter vs Clean AC Filter

3. Do you have any pets?

Regardless of the size of your household, adding one cat or dog to the equation means you should replace your air conditioning filter at least every 60 days. The filter may need changing even more frequently if you have several pets, even in a single occupant household.

4. Do you have carpets?

Carpets can trap more dust and hair than wood or tile, which can end up back in your air conditioning filter.

5. Do you smoke tobacco inside?

Smoking indoors will cause your air conditioning filter to fill up faster, so you’ll need to replace it more frequently.

6. Do you often burn candles inside?

Burning candles and incense also reduces the life of your air conditioning filter.

7. Does anyone in your household have severe allergies?

If someone in your family has sensitive allergies, changing your air conditioning filter more frequently can help reduce their symptoms inside your home.

8. The size of your system’s air conditioning filter

Smaller air filters will fill up faster than systems that use larger sizes. 20 x 20 x 1 is the standard size, so you can judge whether your system uses a small or large filter.

9. What grade air conditioning filter you buy

If you have a pet (or a few), or someone in your household has allergies you may get higher grade air filters. They can help you improve the indoor air quality of your home, but sometimes they can fill up faster because they’re removing more particles.

How Often Should I Replace My AC Filter?

How often you should change your air filter depends on your combination of the above factors.

A three person household in an “average” new construction home with no pets should replace the air conditioning filter every 90 days. A single person could even change their air filter less frequently.

A single occupant with no pets could change their air filter every six months.

For every pet you have in the household, you should replace the air filter 30 days sooner.

A household with one dog or cat should change their air conditioning filter every 60 days. The more pets you have, the more frequently you’ll need to replace the air filter.

Do you have a vacation home that you don’t occupy full-time? Depending on how often you use the system, you could change the air conditioning filter every 6-12 months.

What Does Your AC Filter Do?

You shed 500 million skin cells and up to 100 hair follicles every day.

Multiply that by the number of people in your household, and any pets you may have.

Your air conditioner sucks air from inside of your home for processing inside the unit. Without the air filter, all of those millions of dead skin cells would get blown back through your AC unit.

The air conditioning filter protects the inner mechanics of your HVAC system from getting gunked up with all of those dead skin cells.

On top of that, it also prevents airborne allergens like mold, pollen, and dander from being distributed in your home.

Think of your air filter like a sponge.

The air filter gets more and more saturated as it does it job. Eventually, it becomes too full to “soak up” any more dirt.

Your air conditioner loses 5-15% of its effectiveness when the air conditioning filter is too full.

Why Do You Need to Change Your AC Filter?

Your air conditioner works by pulling air from the inside of your home and passing it through the evaporator coils.

Evaporator coils are the metal A-frame that sits behind your air filter. Your AC uses the refrigerant to make these metal coils cold.

One of your air conditioner’s jobs is to remove water vapor from the air in your home, or “dehumidify” it. Water vapor is the gas form of water, and there’s some amount of it in almost all the air outside.

When your AC passes the airstream over the cold evaporator coils, this cools the water gas and makes it denser, turning it into water.

The water droplets collect on the evaporator coils then drip into the condensate drain pan below.

What Happens If You Don’t Change Your AC Filter?

Your air conditioner is calibrated to work under specific conditions.

Your unit needs just the right amount of water to collect on the coils, just the right volume of air passing over the evaporator coils, and just the right air pressure to work properly.

A dirty air conditioning filter allows less air to pass through the evaporator coils.

Your unit usually depends on the coils becoming saturated enough for water to drip off.

When there isn’t enough air passing over the coils, water droplets can hang out on there too long. This is a problem because water that stays on the coils too long can freeze instead of dripping into the condensate pan.

One of the main causes of an air conditioner freeze is a dirty air filter! Be vigilant about changing the air conditioning filters when they’re dirty.

Air Conditioning Maintenance and Repair in Central Florida

Have you experienced an AC Freeze because of a dirty air conditioning filter? Do you need advice on how to run your HVAC system most efficiently? Schedule an appointment online with us today.