When Should I Change My Air Conditioner's Air Filter at Home?

February 26, 2015

Looking for the fast answer? See our FAQ on "How often to change the air filter".

Every once in a while we’re asked what is the best thing that Clearwater area homeowner's can do to secure their air conditioning and heating system between their scheduled tune-ups? Our advice is simple; remember to change the heating and air conditioning air filter. Replacing furnace and return air filters is crucial to the proper performance of your HVAC system, plus your home's air quality. Research suggests that indoor air pollution is among the top five environmental health risks? You probably don’t consider it as you sit and watch TV, but this is the air you breathe day and night. Changing the air filters is not all that hard for most Clearwater homeowners, but there are typically two hurdles to actually completing this job:

Determining just how often to change your furnace or air conditioner filter.
Replacing them at the proper time.

When To Change Your Air Filters

Most filters have a printed "expiration" date on the box or plastic. It may read "Lasts up to 3 months" or "Change filter every 90 days". Pay attention at the store and you'll notice that some are meant to only last a month, while other manufacturers (like Honeywell) have released media air cleaners with filters meant to be exchanged once every 6-12 months. The norm seems to be once every 3 months for most higher quality filters, but we have a rule of thumb that we suggest our readers to go by. If they're dirty, change them! A dirty air filter can contribute or cause damage to costly equipment, like your compressor, so it's best to change it out more often than neglect it. If you want to stick to the manufacturer's recommended limit, we suggest marking the date on the filter when you swap it out, and programming a reminder for yourself in your phone or on a calendar. Also note that your filter manufacturer sometimes has a different recommendation from your HVAC system manufacturer.

Determining how often to change your air filters can depend on several factors:

The type of air filter you are using
The collective air quality of your Clearwater area home
Pets – Cats, dogs, birds, etc.
Number of people in the home
General air pollution in the Clearwater area or construction taking place nearby

For your typical 1"-3" air filters, the manufacturers basically say to change them bi-monthly, which is actually a great rule of thumb. Still, generalities may not be suitable for your specific needs. If you have to tolerate light to moderate allergies, you might need to upgrade your air filter or change them even more often than OEM specifications. On the other hand, if you're in a less populated area, own a seldom occupied home (like a vacation home) or an area with few automobiles and trucks, replacing your air filters each year may be quite sufficient. Why should you factor in your pets? They have a tendency to shed, which can clog your air filter quick. Naturally, the air filter is just doing its job by containing pet hair and dander, but extremely dirty filters can cause diminished HVAC performance.

In summary:

Seldom used home or single occupant homes without pets or allergies: Change 6-12 months
Common suburban home without pets: Change every 90 days
Got a cat or dog: Change every 60 days
Multiple pets or have allergies: Change every 30-45 days

How To Remember To Change Your Air Conditioner's Air Filters

Midway Services offers a simple solution; sign up for the Service Experts Email Club. This is a great to receive discounts on service, tips and other helpful information directly to your email. Also, your email subscription preferences let’s you set a reminder to change your Clearwater area home's air filter every 30, 60, 90, 120 or 365 days, or any date you find most convenient.

How to replace your return air filter

Most of you know how to replace the air filter in their equipment, but some homes have an extra filter in the return vent. Whether you have one or not is dependent on which HVAC system you have. Your unit is made to handle a certain amount of pressure in your house, and the more filters you have the fiercer the blower motor works, which can reduce the lifespan of your system if it isn't designed for it. Finding out whether you have a return filter and replacing it is simple:

Locate your return air vents.
Some covers have screws and some have tabs. Unscrew or pull tabs to pull off the wall.
Inspect for a filter. If one is there, pull it out and note the size.
Verify the filter type is the one recommended by the manufacturer.
If filter is dirty, replace with the manufacturer's recommended filter of the same size and type.

Crazy as it may seem, filters can really alter your home's airflow, which is why we recommend checking in with the manufacturer. A more expensive HEPA filter that is designed to catch finer particles will obstruct airflow more than a cheaper filter. With restricted airflow comes more pressure on your system, so you ought to verify that your HVAC system was made to handle it. Otherwise, you may experience lowered heating and cooling efficiency in your home, and system parts may break down much faster than the standard.

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