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What You Need to Know About MERV Ratings

A homeowner replacing the filter inside of their central cooling system

What Do I Need to Know About MERV Ratings?

How clean is your home's air, really? Did you know that having an air filter doesn't always mean that your air is being as filtered as you'd like? Different levels of air filters provide various forms of protection and depending on your needs, you may require a higher rating.

MERV ratings are the number of filtrations applied to HVAC air filters. They determine what level of contaminants are filtered through a system before entering a home. There are three primary types of MERV filters used in residential homes. In this blog post, we'll help you learn the difference and choose the right type of air filter for your heating and air conditioning system.

What are MERV Ratings on Air Filters?

This measurement system determines the rate that an air filter catches various types of particles between the size of 0.3 and 10 microns (µm). These types of particles range from dust mites and mold spores to car exhaust emissions and airborne bacteria.

MERV stands for Minimum Efficiency Reporting Value. Home air filters have a MERV rating between 5 and 13. Many units, especially ones installed over 10 years ago, have a MERV rating of 5, which isn't considered efficient by today's standards.

MERV and IAQ (Indoor Air Quality)

Let's address some of the most common home air filter MERV ratings and how effective they are. Understanding this can help you identify whether your current filter is suitable for your home. If your household is experiencing signs of bad indoor air quality, then upgrading your filter to a higher MERV rating could help.

  • MERV 1-4: Less than 20 percent of all particles.

  • MERV 5: 20 to 34 percent of particles filtered.

  • MERV 6-8: 35 to 85 percent of particles filtered.

  • MERV 7-13: 85 to 90 percent of particles filtered.

The biggest sign that your HVAC needs a better MERV filter is that you experience signs of poor indoor air quality. These include asthma or allergy symptoms, a runny nose, sinus problems, headaches, and dust build-up.

Central Air Conditioning Services in Oxnard, CA

At West Coast Air Conditioning, we can help pinpoint the cause of bad indoor air quality in your home. Our experts can also make personalized recommendations on the best MERV rating for your area as well as offer any suggestions on how to improve the efficiency of your heating and cooling system.

Call us at call (805) 954-9195 to speak with one of our skilled Ventura County technicians! You can also contact us through our site using this form.