Where Is a Furnace Filter Located?

February 28, 2023

Changing an air filter is one of the most important, and simplest, HVAC maintenance tasks. But you need to know where the furnace filter is located before you can do anything. It should be changed every 90 days to maintain airflow and keep the system running efficiently. We will now explain how to find the furnace filter so you can go about changing it.

Find Your Furnace

To locate the furnace filter, you first need to find your furnace. It’s usually in a centralized location in the basement, garage, or a utility closet. In homes without a basement, the furnace may be in the attic or a crawlspace. It is often installed near the water heater, washing machine, or other large appliances and equipment.

How to Find the Furnace Filter

The filter is usually inside a metal casing. It’s often in the blower compartment in the path of the airflow so dust, pollen, dander, and other airborne particles can be removed. These build up over time and can cause your furnace to struggle to produce warm air. Therefore, it’s important to clean or replace the filter regularly.

The exact location of the filter depends on the type of furnace you have. These are some of the most common places you’ll find it:

  • Bottom Half of the Furnace: Look behind a metal door at the bottom (the top and bottom doors will need to be opened) if you have a vertical HVAC unit that moves air upwards.

  • Top Half of the Furnace: If it’s a vertical unit that moves air downwards, open the top door to access the air filter, which is installed near the blower (such a furnace often uses two filters).

  • On the Side of the Furnace: If your HVAC unit is configured horizontally, the furnace filter will slide into a rack on the intake side, or in a dedicated sliding compartment next to the air handler.

If you can’t find where the furnace filter is located:

  • Remove the Furnace’s Front Cover: When you’ve found no evidence of a filter on the exterior of the furnace, try removing the front cover. The cover on some models is easy to remove. For others, you’ll have to remove the screws or latches first. The filter should be in a slot behind the front cover. Just remember to turn the furnace off before starting.

  • Check a Ceiling Return Vent: This large vent pulls air back into the HVAC system. It may have a filter installed. Sometimes a vent filter is used in place of a furnace filter. If this is the case, you’ll have to check each return vent; to replace the filter, unlatch its cover, remove the old filter, and insert the new one.

Changing the Furnace Filter

Before replacing a furnace filter, obtain one that’s the same size and type. The furnace must be off before you can safely access the old filter. Slowly pull the old filter out to avoid damaging the housing. The new filter will have an arrow pointing in the direction of airflow, toward the inside of the furnace compartment, to allow proper filtration and airflow. Insert the filter in its correct orientation, close the door, and turn the furnace back on.

Service Champions Can Help Find Where a Furnace Filter Is Located

Every HVAC system has a filter so the tips above should help you find it. If all else fails, you can contact us and our experienced technicians will answer your questions. At Service Champions, we offer professional furnace maintenance so you receive annual heating tune-ups in Northern California. Maintaining your furnace year-round will increase its performance, efficiency, and longevity. To request maintenance, schedule your visit online or call 833-600-0991 today.

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