Locating your Furnace Filter


One of the most frequently asked questions when it comes to heating and cooling elements within a home is, “Where is my furnace filter located?” When you move into a brand new home and need to change out the furnace filter, or if you have lived in your home for a couple of years and feel like it might be time, you may have difficulty finding the furnace filter. Still, you know that it is in there somewhere because every heating and cooling system in a home has a furnace filter. So where is the silly thing hiding?

The location of your furnace filter is typically located somewhere close to where the fan is located. This applies to all different types of heating furnaces, including gas furnaces, oil furnaces, electric furnaces, as well as air conditioners. Even individuals who have been working in the HVAC industry for a number of years occasionally have difficulty when it comes to locating tricky hidden furnace filters, but they are always there somewhere!

Furnace filters can be found behind panels, inside the opening of a duct, or even behind other equipment to keep them completely shielded from view. The original purpose behind furnace filters was simply to prevent stuff from damaging components by getting into the fan section of the furnace, which is why furnace filters can be practically anywhere as long as they are upstream of the fan to a degree. Manufacturers of furnaces and furnace filters usually choose a designated location where their filters can be installed just in front of the fan components.

Oftentimes you will find furnace filters are located somewhere within the duct system, somewhere upstream of the air handler location. This furnace filter location is common when it comes to older heating and air conditioning systems. The best place to start is at the location of the air handler, and to work your way back from that point until you find the furnace filter because it can be pretty much anywhere. Sometimes you will find it at the return air grill opening, and sometimes you will find it behind the return air grill itself.

Once you have figured out which duct is the furnace return duct, you should be in business. Find the grill opening that draws air into it; this is your return duct. The furnace filter will be somewhere nearby this opening, and between it and the air handler.

Keep in mind that there is also the possibility that no furnace filter was installed when the entire unit was originally installed. It may have been removed but not replaced, or it may never have been installed, to begin with. If this is the case, have your furnace officially examined to ensure that everything is still safe. Without a furnace filter, the airflow in your furnace is likely very poor, which can cause safety issues. This is of course in addition to causing inefficiency in your heating and cooling equipment.

Poor airflow can cause a lot of problems in your furnace. If your heat exchanger heats up too much, it can warp or crack. This can cause a carbon monoxide leak or possibly even causing a fire. There is no telling what safety issues you may be caused by failing to ensure that you have a furnace filter in your furnace and that it is properly maintained at all times. Call Auchinachie Plumbing, Heating, and Air with any questions you may have.

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