Simply put a Merv rating is the standard by which all air filtration systems are judged.
The Merv rating stands for minimum efficiency rating value, and is performed by an independent lab, not a filter manufacturer. MERVs, report a filter’s ability to capture larger particles between 0.3 and 10 microns (µm). The rating is derived from a test method developed by the American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE).
This test makes it simple for the homeowner to know what to look for when they are making a air filtration filter choice at their local hardware store. Merv ratings range from 1 to 20 but anything above 13 is really considered hospital grade air filtration and not necessary in the typical residential home. Anything below an 8 on the Merv rating and you’re probably still gonna notice a lot of house dust. Typically a residential home should be purchasing a filter that has a Merv rating between 8 and 12 depending on your needs and the furnace system that you have.
You can find out more about the Merv rating system by going to this link at The American society of heating, refrigeration, and air-conditioning engineers.
Air Flow & MERV Rating
It is very important to consider airflow when purchasing your air filtration. As discussed above Merv ratings come from 1 to 20, and the closer to 20 you get means the filter is much thicker and harder for air to pass through it. This is why it is typically recommended not to go above a Merv 11 or 12 with a newer furnace system. These furnace systems have secondary coils in them which can trap dust and when combined with a higher Merv rating filter can cause airflow problems and potentially damage your furnace. The same holds true for any furnace system that has central air conditioning installed, if you have air-conditioning it means you’re going to have a coil that sits right above your furnace that also traps dust and reduces airflow.
It is also a good idea to change your filters more regularly maybe even once every months if you have a high-efficiency furnace and an air conditioning system, do you want to make sure your filter is good and clean to avoid any potential airflow problems.
Regular air duct cleaning services are required more often if you have a high-efficient furnace or an air conditioning system on your mid efficient furnace system. If you’re looking for air duct cleaning services Spruce Grove for Stony Plain go to our handy flat rate pricing system estimator located here.
Air Filters & MERV Ratings
Most air filter manufacturing companies will post their Merv rating on the side of the filter. Some companies such as 3M, and Kirkland filters, the ones you get at Costco Sometimes will not have the Merv rating listed. You can go onto their website to find out the Merv rating. Always look for this number when you’re making your air filter selection.
When you go to install your air filter in the furnace make sure the arrow is pointing towards the furnace, the arrow represents the direction of airflow.
It’s a good idea to get a logbook or tape a sheet to your cold air return marking down the date that you last changed your filter. Another good way to keep track of this is right the date on the filter were you can easily see it.
We hope this helps with your understanding of the Merv rating system and how to choose proper air filtration for your home.