Your choice of air filter directly affects your HVAC system's performance and reliability, because the filter captures potentially-harmful airborne particles so they don't collect on sensitive components.
Unless your HVAC system has been modified for an electrostatic filter, it likely takes mechanical filters, which are available in both disposable and washable versions. If you currently use disposable filters, you may be wondering whether you can benefit by switching to washable filters. Before you decide, it's good to learn how the two filter types compare in terms of efficiency, maintenance, performance and cost.
The filtering capabilities of both disposable and washable filters are measured using a MERV rating. Some of the most common types of filters used are:
- Flat-panel fiberglass disposable filters that have low MERV ratings of 1-4, which means they're only capable of capturing particles bigger than 10 microns in size.
- Washable mechanical filters also have MERV ratings of 1-4, so they can only trap larger particles like dust mites, lint and pollen.
- Pleated disposable filters with MERV ratings ranging from 5-16. These filters can catch smaller particles down to one micron, such as dust mite droppings, mold spores and pet dander.
Washable air filters are reusable, but they do require monthly cleaning. They must be dried thoroughly too, because putting a damp filter into your HVAC system can lead to bacteria and mold growth. Disposable filters don't need any maintenance – you just discard the dirty filter and replace it with a clean one when necessary.
Even with monthly cleaning, washable filters gradually clog up over time. This means they become more resistant to airflow, which can cause have a negative impact on your HVAC system's performance.
Washable air filters can be reused for several years, but they cost more than disposables that have higher MERVs and better filtering abilities.