How Often Should You Change Your HVAC Filter?

In general, most air filter manufacturers and HVAC companies recommend changing your 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. The only way to ensure how often you need to change your air filter is to perform a visual inspection of the filter every month. After a few months, you'll get an idea of how quickly it gets dirty.

You'll need to reassess if you have a new pet or if the outdoor air quality has been poor. A general rule of thumb for pleated air filters (such as those manufactured by FilterBuy) is to replace the filter every 90 days. As the filter traps more dirt, dust and allergens from the air, the efficiency of the filter decreases.

If you wait too long to change the filter, indoor air quality will suffer.

Households with a pet should generally replace filters after two months; those with more than one pet may need to replace the filter once a month. If your dirty air filter is completely covered with dust and dirt, it's a good idea to change the filter even if it hasn't reached the end of its recommended life. More cycles mean more filter passes and opportunities to trap contaminants, so filters typically fill faster during periods of heavy use.

If there is no smoker or pets in your home, and your filter is the 1 filter that is commonly sold with a MERV rating of 4, you should be able to wait up to 90 days before changing it.

Investing in a relatively inexpensive air filter and replacing the filter at the right time can save you a lot of money on repairs. The fabric of the air filters included in this class makes it much more difficult for the HVAC system to operate smoothly. However, the smaller the appliance used for cooling, the small space usually comes with smaller filters, so you may need to change the filter as often as a filter in a larger home. If you don't like the idea of throwing out the air filter every two weeks, invest in a washable air filter. The deeper the folds, the more surface area the filter has and the more space it has to collect airborne particles, so it may not clog as quickly as a flat filter.

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. All the air that circulates through your HVAC system, whether for heating or cooling your home, will eventually pass through the air filter.

Changing the air filters in your HVAC system is an essential practice that ensures that clean air circulates throughout your home. It involves loosening the screws that hold the filter cover in place if it is located behind a return air vent or simply pulling the filter out of a slot if it is on the side of the oven. You will need to change your HVAC filter more often when you have allergies and asthmatics.

The longer the filter is in place, the more dirt, dust and allergens are trapped, clogging the filter and decreasing its efficiency.

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.

Shana Gojcaj
Shana Gojcaj

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