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Bryant 820SB / 821SB 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:
| 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.
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.
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 Bryant 820SB / 821SB
Last checked 2026-11-02. Manufacturers revise documents. If your unit's label disagrees, trust the label.
8. Turn on electrical supply to furnace. b. Remove screws securing cutoff plate and remove cutoff plate
from housing.
Table 19 – Filter Size Information - In. (mm) c. Loosen set screw holding blower wheel on motor shaft (160+/-20
FILTER SIZE in.-lb. when assembling).
FURNACE FILTER
SIDE BOTTOM d. Remove bolts holding motor to blower housing and slide motor
CASING WIDTH TYPE
RETURN RETURN out of wheel (40+/-10 in.-lb. when reassembling).
16 X 25 X 3/4 14 X 25 X 3/4 e. Remove blower wheel from housing.
14-1/2 (368) Washable* f. Clean wheel and housing.
(406 X 635 X 19) (356 X 635 X 19)
16 X 25 X 3/4 16 X 25 X 3/4 10. Reassemble motor and blower by reversing steps 9a, through 9e. Be
17-1/2 (445) Washable* sure to reattach ground wire to the blower housing.
(406 X 635 X 19) (406 X 635 X 19)
16 X 25 X 3/4 20 X 25 X 3/4 11. Verify that blower wheel is centered in blower housing and set
21 (533) Washable*
(406 X 635 X 19) (508 X 635 X 19) screw contacts the flat portion of the motor shaft. Loosen set screw
16 X 25 X 3/4 24 X 25 X 3/4 on blower wheel and reposition if necessary.
24 (610) Washable*
(406 X 635 X 19) (610 X 635 X 19) 12. Spin the blower wheel by hand to verify that the wheel does not rub
* Recommended
Bryant 820SB / 821SB 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.
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.
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.
Manufacturer document for Bryant 820SB / 821SB (https://www.shareddocs.com/hvac/docs/1009/Public/0D/II820SB-01.pdf), last checked 2026-11-02.