Using your K&N HVAC filter is easy. First, turn off your HVAC system before installing or removing the filter. Place the 20 x 20 x 1 filter in the designated filter slot, making sure it fits snugly. When it comes to maintenance, keep an eye on the filter. Once it looks dirty, it's time to clean it. Remove the filter from the system, gently vacuum off the large dust particles. Then, wash it with mild soap and lukewarm water. Let it dry completely before reinstalling. Avoid using harsh chemicals or scrubbing too hard as it may damage the filter. With proper care, your K&N filter will serve you well for a long time.