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Furnace filter size by brand

Rheem furnace filter size

Most furnaces do not print the filter size on the furnace label. The filter is sized to the opening the installer built, so the reliable answer is the edge of the filter you have now. Rheem and Ruud are made by the same company, Rheem Manufacturing.

Where to look

  • A slot on the side or bottom of the furnace, behind a small cover.
  • A rack on the return duct right next to the furnace.
  • Behind a return grille in a wall, ceiling or floor. Some homes have more than one.
  • A deep media cabinet a few inches thick between the duct and the furnace.

The filter can be in a slot on the furnace, a rack on the return duct, or behind a return grille. Check all three before you assume.

The rating plate

The furnace model and serial number are on a rating plate, usually inside the blower door. Your HVAC company can use them to look up the cabinet, but the printed edge of your current filter is still the quickest answer.

Not sure? Check the printed edge of the current filter, or measure the slot and use the size finder.

Rheem filter questions

What size filter does a Rheem furnace take?

It depends on how the return duct was built, not on the Rheem badge. Read the size printed on the edge of the filter you have now, or measure the slot and round each side up to the next whole inch.

Where is the filter on a Rheem furnace?

Check a slot on the side or bottom of the furnace, a rack on the return duct right next to it, any return grilles in the walls or ceiling, and a deep media cabinet if there is one.

Can I find the filter size from the Rheem model number?

Not reliably. The model number describes the furnace cabinet, while the filter is sized to the opening the installer built. Your HVAC company can look it up from the model and serial number on the rating plate.

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