24
Table 6 – Filter Media Pressure Drop (Clean) V ersus Face Velocity-- In. W.C. (Pa)
Face Velocity
Factory-Accessory
Washable
Representative After-Market Filter Media*
Fiberglass* Pleated*
FPM (m/s) (1-in. / 2.5 cm) (1-in. / 2.5 cm) (2-in. / 5 cm) (1-in. / 2.5 cm) (2-in. / 5 cm)
200 (1) 0.04 (10) 0.05 (13) 0.08 (20) 0.18 (47) 0.12 (31)
300 (1.5) 0.05 (14) 0.09 (22) 0.13 (34) 0.30 (75) 0.21 (52)
400 (2) 0.07 (17) 0.13 (32) 0.20 (50) - - 0.31 (78)
500 (2.5) 0.08 (21) 0.18 (44) 0.27 (69) - - - -
600 (3) 0.09 (23) 0.23 - - - - - - -
700 (3.6) 0.10 (26) 0.29 - - - - - - -
See Table 7 for filter size details.
Table 7 – Air Filter Selection and Duct Sizing -- In. (mm)
FURNACE C ASING WIDTH
FILTER SIZE
FILTE R TYPE
SIDE RETURN BOTTOM RETURN
14--- 3/16{ (360)
16 x 25 x 3/4
(406 x 635 x 19)
14 x 25 x 3/4
(356 x 635 x 19)
Washable*
17--- 1/2 (445)
16 x 25 x 3/4
(406 x 635 x 19)
16 x 25 x 3/4
(406 x 635 x 19)
Washable*
21 (533)
16 x 25 x 3/4
(406 x 635 x 19)
20 x 25 x 3/4
(508 x 635 x 19)
Washable*
24--- 1/2 (622)
16 x 25 x 3/4
(406 x 635 x 19)
24 x 25 x 3/4
(610 x 635 x 19)
Washable*
* Recommended to maintain air filter face velocity. See Product Data for part number.
{ Not all families have these models.
Air Filter Located in Filter Cabinet
FILTER CABINET H EIGHT --- IN (MM) F I LT E R S I Z E --- I N ( M M ) FILTE R TYPE
16 (406)
(1) 16 x 25 x 3/4*
(406 x 635 x 19) or
(1) 16 x 25 x 4--- 5/16
(406 x 635 x 110)
Washable or Media*
20 (508)
(1) 20 x 25 x 3/4*
(508 x 635 x 19) or
(1) 20 x 25 x 4--- 5/16
(508 x 635 x 110)
Washable or Media*
24 (610)
(1) 24 x 25 x 3/4*or
(610 x 635 x 19) or
(1) 24 x 25 x 4--- 5/16
(610 x 635 x 110)
Washable or Media*
* Filters with a side return--- air may have a different filter size. Measure the filter to obtain the correct size.
* Recommended to maintain air filter face velocity. See Product Data for part number.
922SA