We suggest checking filters monthly. If you have a disposable type filter, (these usually have a cardboard edge), and if it is dirty, just replace it. Don't attempt to clean it. Some higher efficiency 1" pleated air filters can go up to three months before needing replacement. But in the higher-use seasons, it's better to check more often.
Different systems have different filter locations. If you don't know where your filter is located, now would be a good time to learn! Usually, there is a removable filter access door in the return air duct next to the furnace or indoor unit. This can be in a basement, crawl-space, utility closet, garage, or attic.
Sometimes, especially with older systems, the filter is located inside the furnace itself, next to the blower motor. And some systems have a central filter grille installed in a wall or ceiling. The grille swings open, revealing the air filter.
Keep in mind, many air filters are directional - the air is meant to flow through the filter in one direction only. Look for an arrow or airflow symbol indicating direction. The arrow should point towards the furnace or air handler. If your filter does not have any arrows, see if one side of the filter looks rougher than the other side; that would be the side to collect the dust, so the other side would face the equipment.
If you have a permanent-type (non-cardboard) air filter, it is very simple to clean. Just follow the four simple steps below...
Step 1 - With the thermostat in the off position, locate and remove your air filter.
Step 2 - Using a garden hose with good water pressure, spray off the filter - from both sides. You can repeat this process several times if the filter is very dirty. Just be careful not to use too much pressure or damage could be done to the filter media. When the water runs clear and the filter is clean you are ready for the next step.
Step 3 - Shake off the excess water. It is a good idea to let the filter sit out and completely dry before reinstalling it. But if it is still a little damp, you can go ahead and re-install it.
Step 4 - Slide the air filter back into the rack, noting proper airflow direction, and you are done. Now you can turn your thermostat back on and remember to do this again next month.
Important Notes...
Some systems, especially larger ones may have more than one air filter. They can even be different sizes.
If you have more than one heating and/or air conditioning system, then you definitely have more than one air filter.
