For Merv 8, 11 and 13 filters, it is recommended to change the filter at least every 3 months for optimal filtration and healthier air in your home. However, if the air filter is made of fiberglass, experts suggest changing it every 30 days. Pleated filters can last up to three months or six months, while a general rule of thumb is to replace them every 90 days. As the filter accumulates more dirt, dust and allergens, its efficiency decreases.
In general, most air filter manufacturers and HVAC companies suggest changing the air filter 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. If you have pets in the house, you should consider changing the filter every 60 days or 2 months. 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 is easy to check if it is time to replace the air filter. Loosen the screws that hold the filter cover in place if it is located behind a return air vent, or simply pull the filter out of a slot if it is on the side of the oven. When you remove the air filter from the air handling unit, if you hold it close to a light source, you can see if the filter is dirty or clogged; if you can't see the light through the filter, it's definitely time to change it.
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. Cats and dogs lose and have odors that can accumulate in their space, so it is necessary to change the filter every 2 months. Air purifiers improve indoor air quality (IAQ) in your home by grouping air particles together so they get trapped in the oven filter and don't circulate throughout your home. 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.
All the air that circulates through your HVAC system, whether for heating or cooling your home, will eventually pass through the air filter. Simply put, if you have poor air quality outside and inside your home, you will need to replace the air filter more often.