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

February 26, 2015

Want the quick answer? Check out our FAQ on "How often to change the air filter".

Every once in a while we’re asked what is the most important thing that West Chester area homeowner's can do to maintain their air conditioning and heating system between their scheduled tune-ups? That’s an easy one; remember to change the heating and air conditioning air filter. Changing furnace and return air filters is critical to the effectiveness of your HVAC system, not to mention your home's air quality. Did you know indoor air pollution is one of the top five environmental health risks? It’s not thought of often, but it is extremely important to consider. Changing the air filters is not all that hard for most West Chester homeowners, but there are usually two challenges to actually accomplishing this task:

Determining just how often to swap out 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 wrapping. It may instruct "Lasts up to 3 months" or "Change filter every 90 days". Check out the filters at the store and you'll see that some are meant to only last a month, while other manufacturers (like Honeywell) have created media air cleaners with filters meant to be swapped once every 6-12 months. The standard seems to be once every few months for most higher quality filters, but we have a rule of thumb that we recommend our friends, and family to go by. If the filter is dirty, change it! A dirty air filter can exacerbate or cause damage to pricey components, like your compressor, so it's recommended to change it out more often than neglect it. If you want to stick to the manufacturer's recommended limit, we suggest writing the date on the filter when you swap it out, and setting a reminder for yourself in your phone or on a calendar. Also be aware that your filter manufacturer may have 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 West Chester area home
Pets – Dogs, cats, etc.
Number of occupants in the house
General air pollution in the West Chester area or construction taking place nearby

For the common 1"-3" air filters, the OEM specs basically say to change them every 30-60 days, which is really a great rule of thumb. Still, general rules aren't always for everybody. If you have to tolerate light to moderate allergies, you might require an upgraded air filter or change them even more regularly than OEM specifications. On the other hand, if you're in a low population area, own a infrequently occupied home (like a vacation home) or an area with few automobiles and trucks, changing your air filter every 12-months may be quite sufficient. Why do we call out our beloved pets? They have a tendency to shed, which can clog your air filter quick. Obviously, the air filter is just doing its job by containing pet hair and dander, but exceptionally dirty filters can cause weak HVAC performance.

In summary:

Infrequently occupied home or single occupant homes without pets or allergies: Change 6-12 months
Average suburban home without pets: Change every 90 days
Add a dog or cat: Change every 60 days
More than one pet or have allergies: Change every 30-45 days

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

Wesley Wood Service Experts offers a simple solution; sign up for the Service Experts Email Club. This is a convenient way to get money-saving discounts and other helpful information on your smartphone, tablet or desktop. Also, your email subscription preferences let’s you set a reminder to change your West Chester area home's air filter every 30, 60, 90, 120 or 365 days, or a specific date of your choice.

How to replace your return air filter

Most of you know how to replace the air filter in their unit, but some homes have an extra filter in the return vent. Whether you have one or not is dependent on what your unit's manufacturer recommends. Your system 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 life expectancy of your system if it isn't designed for it. Learning whether you have a return filter and replacing it is simple:

Find your return air vents.
Some covers have screws and some have tabs. Unscrew or pull tabs to take off the wall.
Look 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 impact your home's airflow, which is why we recommend referring to the manufacturer. A top tier HEPA filter that is designed to catch tinier particles will restrict airflow more than a cheaper filter. With restricted airflow comes greater pressure on your system, so you need to verify that your HVAC system was engineered to handle it. Otherwise, you could experience uneven heating and cooling efficiency in your home, and system parts may wear out much faster than normal.

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