What is a HVAC return air filter?
A return air filter keeps dust and other debris from entering a heating and cooling system and working properly.
Air must cycle through a HVAC unit to work and heat or cool a home, as air is blown into a house through the vents and pulled into the unit through what is called a Return. The same air is cycled in and out of a house and unit over and over cooling or heating the air. While the air cycles it passes by what is called the condenser and through the evaporator coil.
Both the condenser and the evaporator are much like a car radiator that air must pass through to blow out hot air or blow in cool air. The condenser blows the hot air away from a unit while the evaporator cools air as it passes through it and blows air into a home through the vents.
When Return air filters gets dirty or the evaporator coils become clogged no air can pass through the unit which will often cause it to form ice letting even less air through and stopping the unit from working correctly.
What is a HVAC return filter for?
A Return air filter is essential to keeping a HVAC unit working properly. Changing out the filter should be done routinely. It will depend on the area as to how often, for example desert locations because of all the dust sometimes require the filter to be changed weekly, most often though once a month is standard.
Replacing a Return air Filter
Changing a Return air filter is simple enough, it is most often a large grill that is located on the ceiling or a wall. A hallway is the usual place but it may be located somewhere else. A ladder will often be needed to reach it and unlatch the door that will expose the filter.
The dimensions of the filter will be needed to buy another one. The size of the filter is measured by inches, in width and length. For example a 24X16 Return air filter is 24 inches long by 16 inches wide.