How to Choose an Air Filter
April 01, 2018
Air filters are out of sight and typically out of mind. Yet, they’re an important part of your HVAC system that need your attention. Air filters not only help keep your equipment clean and free of debris, but also help to keep indoor air clean.
Air filters should be changed regularly. We recommend changing them every 1 to 3 months. Spring, is an ideal time to replace them since windows have been closed during the winter months, building up dust and debris throughout your home.
Getting the right filter
There are a variety of air filters to choose from, each serving different purposes, and some designed for specific pieces of equipment.
Lower cost air filters
Washable filters, like their name says, can be washed and reused. This is their main advantage. However, they have a low MERV (Minimum Efficiency Reporting Value) rating because they are designed to protect from large dust particles, but not pet dander, bacteria, or smoke. If they are not meticulously maintained, they can even accumulate extra fungi and bacteria.
Fiberglass filters are not reusable, but they are inexpensive and easy to replace. They have a lower MERV rating as well and are designed more to keep your air conditioner clean than your indoor air clean.
Higher performance air filters
Pleated and polyester filters are similar to fiberglass filters but have a much higher MERV rating. Where fiberglass filters remove less than 10 percent of indoor irritants, pleated/polyester filters remove up to 85 percent. They are especially good for catching dust particles.
HEPA filters are the most expensive filters because they remove over 99 percent of irritants in the air and are especially good for people with severe allergies.
For more information about HEPA filters, or if you’re unsure which filter is best for your home, contact a qualified HVAC technician. Not only is it important to choose the proper air filter, and change it regularly, but it’s equally important to have it installed properly for correct air flow.
Last Updated: September 13, 2023