Every 30 days
In the Phoenix valley, 30 days with low ground cover when the dust is high May through September. In the fall and the spring when with low use you can go longer. There are thermostats that track run time and alert you when to replace the filter. If the return starts whistling, you have need for a new filter. I have found this with high priced filters; many say that they are 90 day filters. There so no such thing in the desert in the summer. They are sold as an Indoor Air Quality (IAQ) product. IAQ can be achieved with better results through other means at close to the same price for maintenance as the high priced filters after the initial investment.
Home owners should replace a filter between 6 month - 1 year .
Most residential hvac filters should be changed monthly. If you smoke, have pets, live on a dirt road, or have allergies, you may need to change it more often. We tell people to change it when they pay their electric bill or mortgage/rent.
Understand that changing your filter like this is like taking care of your car. You will help your system run better and live longer. Plus your utility bills will be less than if you are restricting the intake air because of a dirty filter.
Note too that there are some thicker filters on the market that have a longer life span. We still recommend that they at least be looked at monthly.
For the standard house, we recommend a pleated white filter.
Every area and every system is different. This question should be taken up with a trusted local hvac contractor due to the variations of living conditions and areas. A one inch pleated filter in a smoker’s house with pets and children on a dirt road in a windy area in an old house should be changed at least once or twice a month. An elderly person with no pets or very little visitors and a very good insulated house may need changed once every 3 to 6 months.
Filter replacements could range between 1-12 months depending on the type of filter installed and how you personally feel in the home. Some folks are sensitive to air quality so changing the filters more often results in better indoor air quality and overall better system performance.
Filter Size
1" 1-3 Months
2" 3-6 Months
4" 6-12 Months
If you have an electronic filter system clean the washable part once per month to maintain optimal performance.
We recommend that you should replace your home filter every 30 days. But, if you live with animals, smoke, or have a lot of dirt around your house, you may need to replace it before then.
A good rule of thumb for changing your HVAC filters is every month on the same day you pay for your house.
How often to change your air filters can depend on the following:
the type of air filter you are using
the overall indoor air quality
how many pets are in the home
the number of people occupying the home, and
the level of air pollution and construction around the home
For basic 1"-3" air filters, manufacturers usually direct you to change them every 30-60 days. If you suffer from light to moderate allergies, you could upgrade the air filter or change them [even more often|more frequently|every few weeks]3]. Or, if you’re in a more remote area or less occupied home (like a vacation home) and there are fewer cars around, annually may be often enough.
Here are averages that might help you know how often you should change the air filter at home:
Vacation home or single occupant and no pets or allergies: every 6-12 months
"Average" suburban home without pets: every 90 days
Add a dog or cat: every 60 days
Add more than one pet or anyone has allergies: 20-45 days
A basic rule of thumb is to change your filter every thirty days. This will help your HVAC system stay efficient and produce less wear on the system. The benefit to you is cleaner air in your home and savings on your energy bill. However, if you have a household with a lot of pets, tile or hardwood flooring or live in an area with a lot of dust or high allergies you may change your filter out sooner.