Appliance Repair in Los Angeles | Heating Repair | Air Conditioning

Air Filter FAQs: More to Know Than Just Changing the Filter

Most homeowners have heard the advice to change their HVAC system’s air filter frequently, at least every couple months. It’s good advice, but there’s more to know. Your air filter protects your system from dirt and other airborne matter which would build up inside the system, and traps particles you would otherwise breathe. Air filters can improve your air quality and save you money, too.

The Basics

Air filters come in two sets of dimensions. The actual dimensions of your filter are what you will find with a measuring tape. Nominal dimensions round the actual number to the nearest inch, and are the size of the filter you will buy. If you have questions about what size you need, take your old filter to the store with you and compare.

It’s not recommended to wash your old filters. Most filter media aren’t designed to get wet, and will fall apart. They can grow mold or bacteria once dampened. Vacuuming presents fewer risks, but can damage the filter or re-release particles into the air. It’s best to use a fresh filter each time instead.

More on Filters – MERV and HEPA

MERV means “Minimum Efficiency Reporting Value.” This is an industry created standard used to evaluate the efficiency of filters. MERV ratings go from one to 16, with one as the least efficient.

Not all HVAC systems can handle high efficiency filters. Check the system’s documentation for what ratings your particular equipment allows for. Most systems can handle MERV ratings between eight and 11. Higher ratings require more frequent changing.

High efficiency particulate air filters, or HEPA filters, get a lot of press. Because of how dense a HEPA filter must be, it offers too much resistance for most home systems to handle. Filters rated at a MERV of 12 to 13 come very close to providing the same results as HEPA filtration. The exception is the ability to filter airborne viruses.

For expert answers about air filters, or other home comfort questions, please contact us at EG Appliance Repair San Diego. We’re proud to meet San Diego’s heating and cooling needs!