MERV Filters: With Family Health And Furnace Efficiency At Stake, Making The Right Choice Is Vitally Important
Quality air filters for your furnace are equally important for your indoor air quality and for the efficiency of your HVAC system. You can judge the efficiency of an air filter by looking at its MERV (minimum efficiency reporting value) rating.
Why Are Filters Important?
Air filters perform two important jobs, and high efficiency filters do both of these jobs much more effectively:
Air filters protect your furnace by removing dust and other particles from the air as it enters the system. This dust would otherwise settle in the furnace itself, lowering its efficiency and potentially leading to serious problems in the future.
Filters also protect you and your family by removing particles like dust, pollen, mold spores, pet dander, dust mites and insect waste from the air you breathe.
What Do MERV Ratings Mean?
MERV is a simple way to judge an air filter’s effectiveness. Filters are assigned a rating on a scale of 1 to 20, and higher numbers indicate that a filter does a better job of catching smaller particles. Here’s a basic breakdown of what you can expect from different MERV filters:
MERV 1 to 4: Catch particles larger than 10 microns, which helps protect your furnace but doesn’t do much for your air quality.
MERV 5 to 8: Can catch particles as small as 3 microns. This might be good enough if nobody in your house suffers from allergies.
MERV 9 to 13: Just about right for most homes. These filters can catch particles as small as 1 micron, and offer a pretty good balance between cost and efficiency.
MERV 14 to 16: Catch particles down to 0.3 microns, which means they are extremely efficient, but get clogged quickly and will need frequent changing.
MERV 17 to 20: Are so efficient that they may actually cause furnace problems due to air blockage.