246739-CTG-C-0407
Unitary Products Group
5
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 below.
NOTE:
The filter pressure drop values in the “Filter Perfor-
mance” table shown below are typical values for the type of
filter listed and should only be used as a guideline. Actual
pressure drop ratings for each filter type vary between filter
manufacturer.
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.
2. Air flows above 1800 CFM require either return from two sides or
one side plus bottom.
RECOMMENDED FILTER SIZES
Input/Output
BTU/H
CFM
Cabinet
Size
Side Return
Filter in.
Bottom Return
Filter in.
40/38
1200
A
16 x 25
14 x 25
60/56
1200
B
16 x 25
16 x 25
80/75
1200
B
16 x 25
16 x 25
80/75
1600
C
16 x 25
20 x 25
100/93
1600
C
16 x 25
20 x 25
100/93
2000
C
16 x 25
20 x 25
120/112
2000
D
(2) 16 x 25
22 x 25
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
In.
In.
In.
In.
In.
In.
Upflow
1
3
0
0
0
0
Combustible
Yes
Yes
