How to Locate Your Furnace Filter

It’s important to know where your furnace filter is so you can change it regularly. Some people choose to have a qualified heating professional change their filter for them, but plenty of others do it themselves. Whichever you decide, be sure your furnace filter gets changed at least every three months to ensure efficient movement of heat inside your home.

Why does my furnace need a filter?
As air inside your home is pulled into the ductwork of your HVAC system, a filter works to rid it of particles and debris before it comes into contact with your sensitive furnace components. Additionally, your filter also acts to clean the air that’s pushed out of the furnace before it’s blown into your home, removing pollen, allergens, and dust mites. It’s important to change your filter in order to keep your HVAC system working properly and to keep its components clean. Change once a month for standard 1 inch filters, Every 3 months for 1” pleated filters, and once every 6 months to a year for 5” media filters. This will extend the overall life of your equipment and improve your indoor air quality.

Where is my furnace filter?
Furnace filters can be tricky to find. That’s because there’s no standard setup for a furnace system since installation depends on placement, layout, and space constraints. Since the primary purpose of your furnace filter is to keep anything from getting to your filter fan, you can expect it to be located upstream of the fan itself. If your furnace is less than a decade old, you can expect it to have a designated slot for a filter to be installed.

To locate your filter, start at the air handler and trace the ductwork back towards the furnace until you find the filter. In particularly new furnace systems, the return air grill itself may be home to the filter, sealed at the edges completely to keep airflow contained. Still can’t find the filter? There’s a chance your system doesn’t have one at all. If this is the case, bring in an HVAC professional to check that the cooling coil isn’t dirty, and that the rest of the heating equipment doesn’t need to be cleaned.

How do I change my furnace filter?
Once you locate your furnace filter, you need to measure its size. Your filter can measure anywhere from 1” to 6” in thickness, but the designated slot will determine its ultimate size constraints. If you can’t find measurements printed directly on the old filter, use a tape measure to get its exact size and purchase the closest replacement you can find. Before changing the filter, turn your furnace fan OFF to ensure any dust that’s dislodged doesn’t get sucked into the HVAC system. Most filters can only be inserted one way into the filter slot; check for an air flow arrow printed directly on the side of the filter itself.

Need help locating or changing your furnace filter? Your friends at MTB Mechanical help homeowners all over Charlotte maintain their furnace systems from install to replacement.
Give our technicians a call today at 704-321-9250!