How to Change Your HVAC Air Filter

While an annual inspection by a certified HVAC technician is recommended, changing your unit’s air filter is a task you can do yourself. Taking only a few minutes each time, your HVAC air filter should be changed every three months, or more frequently during pollen season or if you have pets, smoke indoors or suffer from allergies.

For those who are new to dealing with HVAC filters, here’s a quick tutorial on how to change your HVAC air filter:

6 Easy Steps to Check your HVAC Air Filter

Step 1

Since there is already an existing air filter in your system, it should be easy to find. It will be located between the ductwork that brings air into your HVAC system and the body of your furnace. You may need to remove your system’s front access panel to find it. Once you’ve located it, you’ll need to determine what size it is. It should be clearly marked with its size. Often it will be labelled with 16x25x1 (or another dimension) on the cardboard frame surrounding it. Do not remove the old filter until you are ready to replace it!

Some HVAC systems use a Media Filter instead of a traditional air filter. These can be changed less frequently, usually every six to twelve months. If your furnace uses a media filter, you’ll need to order a replacement from the furnace manufacturer or a local dealer.


Step 2

Purchase a replacement filter. Once you know the size you need, you can purchase a replacement at most big box stores. Air filters are available in a variety of filtration levels. The least expensive ones perform basic functions, whereas those with finer filtration capabilities can help reduce the amount of dander, allergens, dust, mould, bacteria and other unwanted particles circulating throughout your home. If you really want to protect your home’s air quality, you can purchase a top-of-the-line filter that is specifically made for your particular HVAC system from a local furnace dealer.


Step 3

Adjust your thermostat to turn off your HVAC System; it should not be operating while you change your air filter.


Step 4

Slowly remove the existing, dirty air filter, paying close attention to the direction it is facing. There may be an arrow on the cardboard border to help identify proper placement. This arrow will represent the direction of airflow. Some filters may use a colour scheme to help you identify correct filter placement, with instructions on the frame or packaging to help you avoid positioning it backwards. The old dirty filter should be removed and disposed of into a garbage bag immediately.


Step 5

Unwrap your new HVAC air filter and insert it into the slot where the dirty filter was removed from. Be careful to install it in the correct direction with the arrow facing the same direction as the old air filter. This arrow should be pointing in the same direction as the airflow. If the ducting bringing air to your furnace is moving from left to right, then the arrow should be pointing from left to right.


Step 6

Securely replace the access panel cover and restart your HVAC system. Dispose of the dirty air filter, taking care to not let its contents waft into the air and onto the floor.


That’s it! This one simple task can help your system perform at its peak efficiency, saving you money on repairs and energy costs while keeping the air in your home as free of contaminants as possible.

How To