Instructions for a Naturalaire Furnace Filter

Naturalaire is a brand of air filter for home heating and cooling systems. The filter fits inside the blower compartment on the furnace, which is a stainless steel box connected to the ductwork. Naturalaire filters come in a variety of sizes to fit different furnace models, so it's important to check the dimensions of the old filter before installing a new one. Furnace manufacturers typically recommend changing the filter once a month to catch dust particles that would otherwise blow into your home.

Step 1

Shut off power to the furnace. A breaker switch is typically built into the side of the furnace, or you can cut off the unit at the household circuit breaker.

Step 2

Open the blower compartment on the side of the furnace, using a screwdriver to turn the screw latches that release the vented cover. On some models the screws may not come out completely. Instead, twist each screw half a turn counterclockwise to disengage the latches and open the cover.

Step 3

Pull out the old filter and check the printing around the frame for the dimensions, for example, "12 x 24." If the dimensions are not printed on the old filter, measure the part with a tape measure and write down the length and width in inches to purchase the correct Naturalaire replacement..

Step 4

Insert the new Naturalaire filter into the compartment with the arrow on the edge of the filter facing inward toward the blower.

Step 5

Close the cover and turn the screw latches to hold the cover in place.

Step 6

Restore power to the furnace.