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Bryant 820SA / 821SA furnace: filter size

Bryant 820SA / 821SA filter sizes: 14 x 25 x 3/4, 16 x 25 x 3/4, 20 x 25 x 3/4 and 24 x 25 x 3/4, as listed in the Bryant 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:

Filter sizes by cabinet / model

Sizes found in the source table
14 x 25 x 3/4
16 x 25 x 3/4
20 x 25 x 3/4
24 x 25 x 3/4

Extracted by script from the linked document. Read the excerpt to see which size applies to which cabinet or return.

Measuring a furnace air filter's edge with a tape measure
Illustration only. Not this manufacturer's part.

Replacement interval

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.

Before you buy

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.

MERV notes

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.

Related models

Where this data came from

Manufacturer document for Bryant 820SA / 821SA
Last checked 2026-10-30. Manufacturers revise documents. If your unit's label disagrees, trust the label.

Excerpt from the source

 8. Turn on electrical supply to furnace.                                             To remove wheel:
                                                                                              a. Disconnect ground wire attached to blower housing.
             Table 14 – Filter Size Information - In. (mm)                                    b. Remove screws securing cutoff plate and remove cutoff plate
   FURNACE                       FILTER SIZE                                                     from housing.
                                                                    FILTER                    c. Loosen set screw holding blower wheel on motor shaft (160+/-20
    CASING                  SIDE           BOTTOM                    TYPE
    WIDTH                 RETURN            RETURN                                               in.-lb. when assembling).
                        16 X 25 X 3/4     14 X 25 X 3/4                                       d. Remove bolts holding motor to blower housing and slide motor
   14-1/2 (368)                                                    Washable*
                      (406 X 635 X 19)  (356 X 635 X 19)                                         out of wheel (40+/-10 in.-lb. when reassembling).
                        16 X 25 X 3/4     16 X 25 X 3/4                                       e. Remove blower wheel from housing.
   17-1/2 (445)                                                    Washable*
                      (406 X 635 X 19)  (406 X 635 X 19)
                                                                                              f. Clean wheel and housing.
                        16 X 25 X 3/4     20 X 25 X 3/4
     21 (533)
                      (406 X 635 X 19)  (508 X 635 X 19)
                                                                   Washable*              10. Reassemble motor and blower by reversing steps 9a, through 9e. Be
                                                                                              sure to reattach ground wire to the blower housing.
                        16 X 25 X 3/4     24 X 25 X 3/4
     24 (610)                                                      Washable*              11. Verify that blower wheel is centered in blower housing and set
                      (406 X 635 X 19)  (610 X 635 X 19)
                                                                                              screw contacts the flat portion of the motor shaft. Loosen

FAQ

What size filter does the Bryant 820SA / 821SA use?

Bryant 820SA / 821SA filter sizes: 14 x 25 x 3/4, 16 x 25 x 3/4, 20 x 25 x 3/4 and 24 x 25 x 3/4, as listed in the Bryant 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. 14 x 25 x 3/4; 16 x 25 x 3/4; 20 x 25 x 3/4; 24 x 25 x 3/4.

How often should I replace the Bryant 820SA / 821SA filter?

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.

Why doesn't my filter measure exactly 16 x 25?

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.

How thick is the Bryant 820SA / 821SA filter?

Every size found in the source table is 3/4 in. thick: 14 x 25 x 3/4, 16 x 25 x 3/4, 20 x 25 x 3/4 and 24 x 25 x 3/4. Pending human review; check the excerpt.

Where does this information come from?

Manufacturer document for Bryant 820SA / 821SA (https://www.shareddocs.com/hvac/docs/1009/Public/00/II820SA-02.pdf), last checked 2026-10-30.