
- Turning the temperature to “off” will stop the furnace from turning on. This will ensure that that loose debris, and even a loose fitting filter, won't be sucked into the duct.
2. Locate your system's filter.- If you still have your furnace manual, it should detail the type of filter you have and where it is located. If you don't have the manual available, a typical location for the filter is in either the blower compartment of the furnace, or in the metal ductwork before the blower fan.
3. Determine the type of filter your system uses.- If available, the furnace manual will also provide information about the type of filter your system requires. Some HVAC systems have metal filters that are reusable and need to be rinsed off to clean. Others are one use only and are made of cardboard and fiberglass. For these filters, the dimensions for the filter are important and can be found in the manual or printed on the cardboard filter frame.
4. Remove old filter and, if necessary, replace with cleaned or new filter.- When removing the air filter, make sure to remember the air flow direction into your furnace. There should be an air-flow arrow on the new filter, and it should be pointed in the direction of your furnace. Once the air filter is out, check for dust, dirt and hairs. If there is visible debris, either clean a replaceable filter or throw out the filter and replace with a new one.
5. Turn the temperature back on.- With the clean or new filter in place, you are now ready to start your system again and enjoy the clean air in your home.