246786-CTG-B-0407
4
Unitary Products Group
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.
APPLYING FILTER PRESSURE DROP TO
DETERMINE SYSTEM AIRFLOW
To determine the approximate airflow of the unit with a filter in
place, follow the steps below:
1.
Select the filter type.
2.
Determine the External System Static Pressure (ESP)
without the filter.
3.
Select a filter pressure drop from the table based upon
the number of return air openings or return air opening
size and add to the ESP from Step 2 to determine the
total system static.
If total system static matches a ESP value in the airflow table
(i.e. 0.20, 0.60, etc,) the system airflow corresponds to the
intersection of the ESP column and Model/Blower Speed row
.
FILTER SIZES
Input / Output
BTU/H
CFM
Cabinet
Size
Top Return
Filter in
60/56
1200
B
(2) 14 x 20
80/75
1200
B
(2) 14 x 20
80/75
1600
C
(2) 14 x 20
100/95
2000
C
(2) 14 x 20
120/112
2000
D
(2) 14 x 20
FILTER PERFORMANCE - PRESSURE DROP INCHES W.C.
Airflow Range
Minimum
Opening Size
Filter Type
Disposable
Washable Fibers
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
In.
In.
In.
In.
In.
In.
In.
Downflow
1
3
0
0
0
0
1
*
Yes
Yes
Yes
NA
Horizontal
0
3
0
1
1
0
0
Yes
Yes
Yes
Yes
†
*
Combustible floor base or air conditioning coil required for use on combustible floor.
