Have you heard your HVAC technician talk about MERV ratings? It stands for Minimum Efficiency Reporting Value and can significantly impact your HVAC system’s efficiency.

We all know that air quality is important, but we often take it for granted. We live in cities with busy streets, factories, businesses, and homes with smokers or pets. All of these things can affect the quality of the air we breathe.

That’s where MERV ratings for air filters come into play. They help protect you from pollutants in your home.

Here’s some helpful information about MERV ratings and how to choose the right one for your HVAC unit.

What is a MERV Rating?

The MERV rating of your air filter refers to the Minimum Efficiency Reporting Value – a standard created by ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) in the 1980s.
MERV calculations rate filter efficiency and are measured in numbers ranging from 1-20, with 20 being the best at filtering out particles from the air.

In addition to promoting better indoor air quality, installing high-efficiency residential HVAC filters can also improve energy efficiency by reducing energy costs associated with heating and cooling your home.

Understanding a MERV Rating

So, what’s the big deal about MERV ratings?

You should care about MERV ratings because they tell you how much dust and allergens your air conditioner or furnace will remove from your home’s air supply. The higher the rating, the better your system will filter out these contaminants.

But sometimes, the highest rating filter isn’t always the best. For example, filtering out the smallest particles with a thicker filter can stress your HVAC system and cause wear and tear. The highest MERV ratings are best in sterile environments like hospitals.

If you have a family with asthma or allergies, look for an air filter with a MERV rating between 5 and 8. These filters can remove enough dust and allergens from the air to make your home more comfortable without sacrificing performance.

MERV Ratings and Their Uses

The MERV rating score is determined by testing how easily particles pass through the filter. The test uses a series of different-sized particles that become trapped as they pass through the filter.

MERV Rating 1-7

Air filters with a MERV rating of 1-7 are used in larger industrial settings where airflow is already good. They’re primarily used to protect machinery by removing larger particles from the air.

Air filters with a MERV rating of 1-7 generally filter particles down to 10-micron particle size.

You may be tempted to use a lower MERV rating to save on energy bills. However, using a higher-efficiency filter for smaller areas like your home makes more sense. You don’t want to breathe in harmful pollutants that can affect your health.

MERV Rating 8-13

If you want to protect your home and improve your indoor air quality, a filter with a MERV rating of 8-13 is recommended. These filters capture particles down to three microns. If you suffer from asthma or allergies, the higher the filter in this range, the better.

The higher-rated filters can help eliminate particles like:
  • Pollen
  • Dust mites
  • Pet dander
  • Carpet fibers

Filters with a MERV rating of 13 can also filter out pollutants like auto fumes and mold spores. A professional HVAC technician can give you more information about the best air filters for your home.

MERV Rating 14-20

The most common MERV ratings in hospitals and labs are above 14. Hospitals tend to use the higher MERV rating to ensure that they have a high level of protection against viruses and bacteria. In addition, these higher-rated air filters can help protect from dangerous particles, including:

  • Tobacco smoke
  • Coal dust
  • Legionella
  • Lead dust
  • Cement dust

Does a HEPA Filter Have a MERV Rating?

HEPA filters are used in many homes and businesses to improve indoor air quality. The acronym stands for high-efficiency particulate air. These filters are specially designed to trap and remove fine particles from the air passing through them.

HEPA filters have a MERV rating of 17 or above. As a result, they remove 99% of all particles larger than 0.3 microns from the air that passes through them.

They also help remove smoke from secondhand smoke and chemicals from household cleaners. This can be especially beneficial for people who suffer from asthma or COPD.

If you have allergies to animal allergens like dust mites or pollen, HEPA filters improve your quality of life by reducing your exposure to these allergens in your home.

Unfortunately, air filters don’t last forever, and they need changing. Most manufacturers recommend replacing your air filter every three months. This routine job can be carried out during an HVAC tune-up.

Need help to decide which air filter is best for your home? Contact the experts at JW Plumbing, Heating and Air today for more information.

company icon