Looking for the short answer? Check out our FAQ on "How often to change the air filter".
Every once in a while we’re asked what is the best thing that Philadelphia area homeowner's can do to protect their air conditioning and heating system between their seasonal tune-ups? Our advice is simple; remember to change the heating and air conditioning air filter. Replacing furnace and return air filters is critical to the effectiveness of your HVAC system, in addition to your home's air quality. Studies show that indoor air pollution is in 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 difficult for most Philadelphia homeowners, but there are usually two obstacles to actually accomplishing this task:
- Determining just how often to swap out your furnace or air conditioner filter.
- Changing them when you’re suppose to.
When To Change Your Air Filters
Most filters have a printed "expiration" date on the wrapping. 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 designed to only last one month, while other manufacturers (like Honeywell) have created media air cleaners with filters meant to be exchanged once every 6-12 months. The industry standard seems to be once every three months for most higher quality filters, but we have a rule of thumb that we tell our readers to go by. If it's dirty, change it! A dirty air filter can exacerbate or cause damage to expensive parts, like your compressor, so it's best to change it out more often than to let it go. If you want to stick to the manufacturer's recommended limit, we suggest scribbling the date on the filter when you swap it out, and setting a reminder for yourself in your phone or on a calendar. Also note that your filter manufacturer might have a different recommendation from your HVAC system manufacturer.
Figuring out how often to change your air filters hinges on several factors:
- Which air filter your system requires
- The entire air quality of your Philadelphia area home
- Pets – Dogs, cats, etc.
- Number of occupants in the house
- General air pollution in the Philadelphia area or construction taking place nearby
For your typical 1"-3" air filters, the manufacturer specs basically tell you to change them every 1 or 2 months, which is in fact a great rule of thumb. But general rules aren't always for everybody. If you have to endure light to moderate allergies, you may need to upgrade the air filter or change them even more often 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 little auto traffic, changing your air filter every 12-months may be quite sufficient. Why should you factor in your pets? They have a tendency to shed, which can clog your air filter fast. Obviously, the air filter is just doing its job by trapping pet hair and dander, but tremendously dirty filters can cause seriously reduced HVAC performance.
- Vacation home or single occupant homes without pets or allergies: Change 6-12 months
- Common suburban home without pets: Change every 90 days
- Add a dog or cat: 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
Here’s an easy way to stay on top of this; sign up for the Service Experts Email Club. When you do, you can elect to receive (or not) great email coupons and newsletters with a lot of tips and discounts on AC repairs and tune-ups. Plus, your email subscription preferences let’s you set a reminder to change your Philadelphia 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 equipment, but some homes have another filter in the return vent. Whether you have one or not is dependent on which HVAC system you have. Your system is engineered to handle a maximum amount of pressure in your home sweet home, and the more filters you have the harder the blower motor works, which can decrease the life expectancy of your system if it isn't designed for it. Finding out whether you have a return filter and replacing it is a piece of cake:
- Go to your return air vents.
- Some covers have screws and some have tabs. Unscrew or pull tabs to remove from the wall.
- Inspect for a filter. If one is in place, pull it out and record 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.
Incredible though it may seem, filters can dramatically alter your home's airflow, which is why we recommend asking the manufacturer. A more expensive HEPA filter that is designed to catch tinier debris will obstruct airflow more than a cheaper filter. With restricted airflow comes increased pressure on your system, so you should verify that your HVAC system was built to handle it. Otherwise, you might experience uneven heating and cooling efficiency in your home, and HVAC parts may die off much faster than normal.