In general, most air filter manufacturers and HVAC companies recommend changing the air filter every 90 days or 3 months. This can vary depending on the location of your home, if you have pets, and the age of your system and equipment. If you have pets at home, it is advisable to switch out the filter every 60 days or every 2 months. For households with multiple pets or people with allergies or respiratory conditions, it is recommended to replace the filter every 20 to 45 days.
Vacation homes or vacant homes that don't get much use usually wait to change filters every 9 to 12 months. The more you use your home, the more often you should change your air filter. Pleated air filters (such as those made by FilterBuy) should be changed every 90 days. As the filter captures more dirt, dust and allergens from the air, its efficiency decreases.
Basic 1 to 3 air filters should be replaced every 30 or 90 days, while fiberglass air filters should be swapped out approximately once every 30 days. Pleated air filters should be exchanged approximately once every three to six months. However, the frequency of air filter replacement depends on several important factors such as the home, the occupants and their location. It is important to inspect your air filter at least once a month to see how dirty it is getting.
If any member of your family has mild to moderate allergies, you can put a better air filter on them or change them even more often. If the dirty air filter is completely covered in dust and dirt, it's a good idea to switch it out even if it hasn't reached the end of its recommended life. The minimum efficiency value (MERV) rating of an air filter measures how effectively the filter prevents dust and other contaminants from passing through the filter and reaching the air stream. Air filters trap pet hair, dust, and other irritating particles so that the air conditioning system returns fresh, clean air to the house.
If you have an asthmatic or allergic person at home, replace the filter every 6 weeks to ensure optimal indoor air quality. Air filters with a MERV rating ranging from 17 to 20 are designed for areas that require absolute sterility, such as operating rooms or rooms for immunosuppressed people. When it comes time to buy new air filters for your HVAC system, most cases require an air filter with a MERV rating of 16 or lower for residential, commercial and institutional HVAC systems. The only type of filters that trap allergens and spores are HEPA filters, or high-energy particulate air filters.
