Understanding Air Filters and MERV Ratings

Your HVAC system has many different components that are crucial for performance and home comfort, but one of the most important is the air filter. A filter keeps the air in your home healthy by trapping airborne particles and contaminants like pollen, dust and other allergens before they can spread through the home. In addition, a filter also keeps dust and debris from harming the more delicate parts of the home’s HVAC system.

It’s important to remember that not all HVAC air filters are the same, and certain filters provide higher filtration capabilities.

What is MERV?
Minimum Efficiency Reporting Value (MERV) is a rating for air filters that indicates how efficiently a filter can capture airborne particles that reduce indoor air quality and trigger allergy symptoms. The higher the MERV, the better it is at catching particles, debris and allergens.

MERV Minimum Particle Size:
The MERV rating scale is based on the minimum size of airborne particles a filter can collect.

MERV Value       Particle Size (in microns)
1 – 4       > 10.0 μm
5 – 8       10.0 – 3.0 μm
9 – 12       3.0 – 1.0 μm
13 – 16       1.0 – 0.3 μm
17 – 20      < 0.3 μm

Which air filter is best?
Different rated air filters will serve different needs. A filter with a MERV rating between 7 and 12 will generally be ideal for most homes, but those with severe allergies will want to consider a filter with a higher MERV rating.

It’s important to keep in mind that a higher rated filter can be too restrictive and significantly reduce airflow, and this can put a strain on your HVAC system while negatively affecting your air conditioner’s performance. It’s best to consult a certified HVAC specialist about which filter will work best for your home and specific needs.

Remember it’s important to regularly maintain filters for optimal performance. Check and replace filters regularly to help ensure your HVAC system is operating at peak efficiency all year long.

Contact Team Harding to learn more about which air filter is best for your home! And be sure to check out our
wide selection of indoor air quality products!

Harding Heating & Air Conditioning has been serving Ottawa and the surrounding area with top-quality service since 1994! We’re committed to our customers and are happy to help you find the best ways to improve your home comfort.

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