The” size issue” of the furnace filter

Maybe you will be confused when you consider changing a furnace, but we will help you figure it out as possible as we can. For this essay, some useful guidance is provided for you when you plan to change your furnace filter in the next time.


Scenario one: Your current filters include dimension


If the old filter is also on your furnace, and there was printed with dimension, it not difficult for you to ensure the size. You can order a new furnace filter according to the old dimensions, but it’s not the actual size of the opening in your furnace where the filter is installed, please remember it. These dimensions represent the “nominal size”, and they are rounded to the nearest inch measurement. The opening dimension means the actual size, most of the companies will reveal the actual dimension when they sell the furnace filters. For instance, if the real size

of the opening is 15 1/2’’ by 24/12’’, which means the nominal dimension of filter you want is 16 by 25.



Scenario two: Your current filters need dimension


If you can’t make sure of the size of your furnace filter, don’t worry about it. It is necessary to measure the size of the opening easily and round up to the nearest inch. For example, if the real size of the opening is 14 by 19 1/2, it means the nominal dimensions are 14 by 20.


Maybe it’s an issue with the size of Furnace filters, and you can refer to the guidance, can work it out. 


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