Unitary Products Group
5
278177-BTG-A-0407
FILTER PERFORMANCE
The airflow capacity data published in the “Blower Perfor-
mance” table listed above represents blower performance
WITHOUT filters. To determine the approximate blower per-
formance of the system, apply the filter drop value for the fil-
ter being used or select an appropriate value from the “Filter
Performance” table shown.
NOTE:
The filter pressure drop values in the “Filter Perfor-
mance” table shown are typical values for the type of filter
listed and should only be used as a guideline. Actual pres-
sure drop ratings for each filter type vary between filter manu-
facturer.
NOTES:
1. Air velocity through throwaway type filters may not exceed 300
feet per minute. All velocities over this require the use of high
velocity filters.
RECOMMENDED FILTER SIZES
CFM
Cabinet Size
Top Return Filter in
1200
A
(2) 14 x 20
1200
B
(2) 14 x 20
1600
C
(2) 14 x 20
2000
C
(2) 14 x 20
2000
D
(2) 14 x 20
FILTER PERFORMANCE - PRESSURE DROP INCHES W.C. AND (KPA)
Airflow Range
Minimum
Opening Size
Filter Type
Disposable
Washable Fiber
Pleated
CFM
in
2
In W.C.
In W.C.
In W.C.
0 - 750
230
0.01
0.01
0.15
751 - 1000
330
0.05
0.05
0.20
1001 - 1250
330
0.10
0.10
0.20
1251 - 1500
330
0.10
0.10
0.25
1501 - 1750
380
0.15
0.14
0.30
1751 - 2000
380
0.19
0.18
0.30
2001 & Above
463
0.19
0.18
0.30
UNIT CLEARANCES TO COMBUSTIBLES
Application
Top
Front
Rear
Left
Side
Right
Side
Flue
Floor/
Bottom
Closet
Alcove
Attic
Line
Contact
Downflow
1
3
0
0
0
0
1"
*
Yes
Yes
Yes
No
Horizontal
0
3
0
1
1
0
Combustible
No
Yes
Yes
Yes
†
*
Special floor base or air conditioning coil required for use on combustible floor.
†
Line contact only permitted between lines formed by the intersection of the rear panel and side panel (top in horizontal position) of
the furnace jacket and building joists, studs or framing.
