Your air filter’s main purpose is to protect your heating and cooling equipment from dirt and dust in the air, but selecting the right filter can also help you breath easier by improving your home’s air quality and reduce energy bills by keeping your HVAC system running efficiently. If you want to make the ideal selection, it’s important to be knowledgeable about air filters.
Minimum efficiency reporting value (MERV)
An air filter’s MERV tells you how efficient it is at removing particles from the air. Higher values are better at removing more and smaller particles. The caveat is that high-end MERV filters can create too much resistance to airflow, causing your HVAC equipment to overwork itself to compensate. This leads to premature wear and tear, as well as inefficient operation. To avoid this, it’s important to know highest MERV filter you system can your system can handle. Residential air filters may have a MERV as high as 16, but for most households experts recommend not using anything higher than a 13. Many homes will require an even lower MERV to run efficiently. Contact an HVAC professional to find out what is best for your system.
High efficiency particulate air (HEPA) filters
These have MERV values as high as 20 and are only used in specialized applications. They have very high airflow resistance and likely will need equipment modifications if installed as part of your heating and cooling system. However, HEPA filters are also available as stand-alone air-cleaning systems.
Air filters should fit in their slot snugly and without any gaps. If you have to force it in, you could damage it. The dimensions should be listed on the currently installed air filter.
It’s simple enough; air filters need to be replaced when they get dirty. Dirty air filters reduce airflow and efficiency. How frequently this is necessary depends on the amount of use, other conditions found in your home and the thickness of the filter. Thick box-type filters may only need replacing once a year, while one-inch filters may need replacing every month. Cleaning filters is not recommended as they can become damaged. Get in the habit of inspecting the filter once a month. If it looks dirty, change it.
For more information on the ideal air filter for your home, contact Paschal Heat, Air & Geothermal. We have been serving homeowners in northwest Arkansas since 1968.
Our goal is to help educate our customers in Northwest Arkansas about energy and home comfort issues (specific to HVAC systems). For more information about air filters and other HVAC topics, download our free Home Comfort Resource guide.
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