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Goodman GMH8 / GDH8 filter sizes: 10 x 20, 14 x 20, 14 x 24, 14 x 25, 16 x 25, 20 x 25 and 24 x 24, as listed in the Goodman source document's filter table. Which size fits depends on your cabinet and return. This page is pending human review, so check the source excerpt below.
Auto-extracted · review pending Filter sizes auto-extracted from the manufacturer document.
Last checked against the manufacturer document:
| Sizes found in the source table |
|---|
| 10 x 20 |
| 14 x 20 |
| 14 x 24 |
| 14 x 25 |
| 16 x 25 |
| 20 x 25 |
| 24 x 24 |
Extracted by script from the linked document. Read the excerpt to see which size applies to which cabinet or return.
General guidance (not from this manual): check monthly and replace 1-in. filters every 1–3 months, or follow the filter maker's guidance and your owner's manual.
Pull the old filter and read the size printed on its frame. Nominal sizes are rounded up: a 15.5 x 24.5 in. filter is sold as 16 x 25.
Match the size or part number printed on your current filter.
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Your furnace manual lists the filter's dimensions, not its MERV rating. Higher-MERV filters restrict more air. Manufacturers such as Carrier recommend keeping the clean-filter pressure drop under 0.2 in. w.c. (ideally under 0.1). Lennox warns that an over-restrictive filter can trip the high limit in winter and freeze the coil in summer. If you want MERV 11–13, a 4-in. media cabinet is the usual route. Ask an HVAC tech to check static pressure. Nominal sizes are rounded: a filter labeled 16 x 25 x 1 actually measures about 15.5 x 24.5 x 0.75.
Manufacturer document for Goodman GMH8 / GDH8
Last checked 2026-10-28. Manufacturers revise documents. If your unit's label disagrees, trust the label.
GMH8 Minimum Filter Sizes
GMH8 GMH8 GMH8 GMH8 GMH8 GMH8 GMH8 GMH8 GMH8
Model #
0403A* 0603A* 0604B* 0803B* 0804B* 0805C* 1005C* 1205D* 1405D*
(1) 16 x 25 (Side) or (1) 16 x 25 (2) 16 x 25 (Side) or (2) 16 x 25 (Side) or
Filter Size (in²) (1) 16 x 25 (Side or Bottom)
(1) 14 x 24 (Bottom) (Side or Bottom) ¹ (1) 20 x 25 (Bottom) (1) 24 X 24 (Bottom)
Note: Other size filters of equal or greater surface area may be used; filters may also be centrally located.
¹ Use 2- 16 x 25 filters on side returns or 20 x 25 filter on bottom return if furnace is connected to a cooling unit over 4 tons nominal capacity.
GDH8 Minimum Filter Sizes
Model # GDH80403A* GDH80603A* GDH80804B* GDH81005C*
(2) 14 x 20 or (2) 14 x 20 or
Filter Size (in²) (2) 10 x 20 or (1) 14 x 25 Top Return
(1) 16 x 25 Top Return (1) 20 x 25 Top Return
Note: Other size filters of equal or greater surface area may be used; filters may also be centrally located.Goodman GMH8 / GDH8 filter sizes: 10 x 20, 14 x 20, 14 x 24, 14 x 25, 16 x 25, 20 x 25 and 24 x 24, as listed in the Goodman source document's filter table. Which size fits depends on your cabinet and return. This page is pending human review, so check the source excerpt below. 10 x 20; 14 x 20; 14 x 24; 14 x 25; 16 x 25; 20 x 25; 24 x 24.
General guidance (not from this manual): check monthly and replace 1-in. filters every 1–3 months, or follow the filter maker's guidance and your owner's manual.
Filter sizes are nominal (rounded). A filter sold as 16 x 25 x 1 actually measures about 15.5 x 24.5 x 0.75 in. Buy by the nominal size printed on the frame.
Yes. The source table lists 7 sizes: 10 x 20, 14 x 20, 14 x 24, 14 x 25, 16 x 25, 20 x 25 and 24 x 24. Which one applies depends on your cabinet and return; check the excerpt (pending human review).
Manufacturer document for Goodman GMH8 / GDH8 (https://cdn.daikincloud.io/PIM/Assets/Documents/SS-GMH8.pdf), last checked 2026-10-28.