There are many reasons for changing your heating and cooling system filters on a regular basis. If you ignore changing them regularly, you may be losing the protection that they offer. Furnace filters can become full of dust, debris and other contaminants, will not capturing the new particles that come through, which allows harmful particles to release into the air and your loved ones will be breathing them in. In addition, your HVAC system will work harder and more energy will be consumed, hence more utility bills.
Now the question arises how do you know when to change the filter? It depends upon the several factors such as Do you have pets? How dusty is your home? Do you keep the heat or a/c fan on? Does anyone smoke in the home? Do you keep windows and doors open? Merv Filters LLC suggests you to change your system filter every month or two, if you are living in any of the above conditions.
With an effective open area of 96%, our 20x25x4 air filter MERV 11 trap and eliminate 91% of airborne particles as tiny as 1 micron. Our pleated MERV 11 filters are crafted using 100% synthetic media, which can withstand in harsh conditions and unaffected by moisture.
Important Note: When you look for air filters online, make sure you get the right size filter. The nominal size of the filter is bit greater than the actual size. For example, if the nominal size of the filter is 20x25x4, the actual size will be 19.5×24.5×3.75