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A High-Efficiency Air Filter Might Spell Disaster

air-fliter-cuAre you interested in better air quality for your home? Chances are that you’d benefit from the professional installation of air cleaners of some type. There are many different types of air cleaning products on the market, ranging from tiny electronic air purifiers that don’t do much to extensive whole-house air filtration and purification systems. Because of the high number of types of pollutants that found in today’s homes, we strongly recommend working with our IAQ professionals to find the ideal air quality products and solutions.

And this brings us to the topic today, which is the simple mistake some homeowners make if they try to go it alone with air cleaners…

High MERV Rating Can Mean a Poor HVAC System

Mechanical air filters are found in most IAQ systems. They’re a basic starting point for removing larger airborne particles, and they don’t require a power source. There are many types of air filters, and their strength is measured as MERV, minimum efficiency reporting value. The higher the MERV, the more efficient the filter at stopping smaller particles. For example, the simple filter that’s found on window AC units has a MERV of around 4. It can stop lint and pet hair and that’s about it. Central HVAC systems often have MERV above 10, and may be as high as 16, which is capable of trapping smoke, chemicals, and particles down to 3 microns in size.

But the thicker the weave of a filter for a higher MERV rating, the more restriction the filter places on airflow circulation. The filter might stop unwanted particles—because it’s stopping the air as well! Some HVAC systems won’t be able to handle a MERV 16 filter. A thick filter that’s too thick will increase pressure in the ventilation system, which will cause the blower fan to cycle down. Airflow from the vents will drop, leading to a steep decline in comfort. The extra strain on the blower as it attempts to overcome the restrictions can lead to the system failing years before its time, and it will drive up bills until it does.

(You’ve probably heard of HEPA filters, which are filters used to help reduce allergens from the air. Although HEPA filters are powerful, they are primarily used in commercial buildings and healthcare facilities, and are rarely good matches for use in homes.)

Find the Right Filters

As you can see, simply picking the filter with the highest MERV rating can end up as a fiasco. Finding the filter that’s right for your house is a job for HVAC professionals familiar with air filtration and purification systems. They’ll install the most powerful filter possible that will still permit the HVAC system to run optimally. If this doesn’t eliminate all the air contaminants, they’ll pair the filter with an electronic air cleaner to target the smaller pollutants. The right combo of air filter and electronic air purifier can remove more than 99% of contaminants from your household air.

Arrange for better indoor air quality today! Wm. Henderson Plumbing, Heating & Cooling Inc. offers air conditioning services to Delaware County & The Main Line, PA.

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