How Often Should You Replace a Merv 8 Filter?

For Merv 8, 11 and 13 filters, it is recommended to change the filter at least every 3 months for optimal filtration. However, if the air filter is made of fiberglass filters, experts suggest changing it every 30 days. On the other hand, expensive pleated filters can work well with a replacement once every three months or six months. The Minimum Efficiency Report Value (MERV) rating for an air filter measures how effectively the filter prevents dust and other contaminants from passing through the filter into the air stream.

In general, filters with a MERV 16 rating or lower are considered HVAC system grade filters for residential, commercial, and general hospital use. A house that is occupied most of the time will require more frequent use of the air conditioning system and therefore will need to replace the filter much sooner compared to a house with no occupants. If you have poor air quality outside or pets indoors, you'll need to replace your air filter more often. For households with multiple pets or people with allergies or respiratory conditions, we recommend changing the filter every 20 to 45 days.

Vacation homes or vacant homes that don't have much use can usually wait to change filters every 9-12 months. It's important to note that there are high-efficiency filters that are designed to filter out small bacterial, mold, and fungal particles, but your standard MERV 8-11 filters will simply block out larger particles of dust, dirt & hair. We recommend doing a quick visual check of your filter every 3-4 weeks if you are unsure of how often your oven filter will be replaced. Simply replacing a dirty filter keeps your system running efficiently, prevents system breakdowns, and can extend the life of your HVAC system. But how often do you need to change the air filter? How often do you need to change the oven filter? Well, it depends on several factors such as location of your home, if you have pets and the age of your system and equipment.