Q&A About Filters for Rheem Furnaces
Question: What are the filter sizes on the Rheem Classic 90 Plus?
Answer: The filter you need depends on both your furnace configuration (upflow, downflow or horizontal) and the width of your furnace's cabinet. See the chart below.
Furnace Filters for the Rheem Classic 90 Plus
Air Flow Configuration | Cabinet Width | Filters |
Upflow | 17-1/2" | 2 15-3/4x25x1 filters |
Downflow / Horizontal | 17-1/2" | 2 12x20x1 filters |
Upflow | 21" | 1 15-3/4x25x1 filter |
Downflow / Horizontal | 21" | 2 12x20x1 filters |
Upflow | 24-1/2" | 1 15-3/4x25x1 filter 1 22-3/4x25x1 filter |
Downflow / Horizontal | 24-1/2" |
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Upflow | 25" | 1 19-1/4x25x1 filter |
Question: What kind of filter do I need for the Rheem Criterion II Plus 2 LXE furnace?
Furnace Filters for the Rheem Criterion II Plus 2 LXE
Air Flow Configuration | Cabinet Width | Filters |
All | 17-1/2" | 2 12x16x1 filters |
All | 21" | 2 20x16x1 filters |
All | 24-1/2" |
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Question: Rheem model RGPH-12earjr filter size
Answer: For your Rheem RGPH filter you need to know your air flow configuration and the width of the front of the furnace cabinet. See the chart below with this information to find the correct filter size you need.
Furnace Filters for the Rheem RGPH
Air Flow Configuration | Cabinet Width | Filters |
Upflow | 14" |
1 12-1/4x25x1
filter
(bottom air return) 1 15-3/4x25x1 filter (side air return) |
Downflow | 14" |
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Upflow | 17-1/2" |
1 15-3/4x25x1
filter
(bottom air return) 1 15-3/4x25x1 filter (side air return) |
Downflow | 17-1/2" | 1 12x20x1 filter |
Upflow | 21" |
1 15-3/4x25x1
filter
(side air return) 1 19-1/4x25x1 filter (bottom air return) |
Downflow | 21" | 2 12x20x1 filters |
Upflow | 24-1/2" |
1 15-3/4x25x1
filter
(bottom air return) 1 22-3/4x25x1 filter (bottom air return) |
Downflow | 24-1/2" |
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