Step by Step instructions on changing a furnace filter

Locate the air Filter. Depending on the furnace design, it can either be located in the blower door unit itself or located between the blower and the return air duct.  You may need a screwdriver to help pry open the access panel or blower door.

Remove the filter from it’s support.

Check filter Hold your filter up to light to check for cleanliness.  If it’s dirty or you’re not sure either replace it or clean it.

Replace or Clean the Filter.  If your filter is paper or fiberglass and it is dirty, then replace it.  If the filter is a dry foam type filter you can wash it out or vacuum it clean.

Insert Filter into Furnace. Look at your replacement filter and notice the arrow on the frame that shows the direction of air flow for the filter.  Insert the filter back into it’s holding frame with the air flow arrow positioned correctly.  The arrow should point towards the blower motor and main part of the furnace.

Replace the access panel or blower door panel.

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