In general, most air filters should be changed every 90 days or 3 months. This may vary depending on the location of your home, if you have pets, and the age of your system and equipment. A good rule of thumb for pleated air filters (such as those manufactured by FilterBuy) is to replace them every 90 days. If you live in a dry and dusty climate, or have pets, you may need to replace your air filter more often.
During a remodeling project, it's best to change the oven filter every 30 days or even more frequently to prevent construction-related dust from circulating around the home. The size of your home also affects how often you should change your air filter. A family of four will need to change their air filter more often than a single person's home. Additionally, filters with higher MERV ratings are denser and require more effort from your oven to draw air through them.
Not all ovens are powerful enough to do so. If you have allergies or asthma, you'll want to change your filter every 6 weeks to maintain the best indoor air quality. Denser filters last longer and have a better MERV rating. If there is a visible layer of dirt that covers most of the filter surface and that is thick enough to hide the filter material itself, it is a sign that the filter has been in the HVAC system for too long.
Typical recommendations range from every 30 days for cheaper fiberglass filters (which often don't do a good job of filtering), to 6 months for high-end pleated filters. One of the advantages of denser filters is not only that they live longer, but they also generate less air resistance, which can help the HVAC system work more effectively and reduce wear and tear on components, including the fan motor. One of the most important things you can do on your own to take good care of your HVAC system is to simply change your air filter on a regular basis. By following these guidelines, you can ensure that your HVAC system runs efficiently and effectively.