175245-YIM-C-1008
Johnson Controls Unitary Products
23
* Factory Setting
Power Exhaust motor is a 3/4 HP, PSC type with sleeve bearings, a 48 frame and inherent protection.
TABLE 15: STATIC RESISTANCES
1
DESCRIPTION
RESISTANCE, IWG
CFM
20 TON
6000
8000
9300
WET INDOOR COIL
0.1
0.1
0.1
ELECTRIC HEAT OPTIONS
18 KW
0.1
0.1
0.1
36 KW
0.1
0.2
0.3
54 KW
0.2
0.3
0.4
72 KW
0.2
0.4
0.6
ECONOMIZER OPTION
0.1
0.1
0.2
HORIZONTAL DUCT CONNECTIONS
2
0.2
0.3
0.5
1.
Deduct these resistance values from the available external static pressures shown in the respective Blower Performance Table (See Note 2 for
exception.)
2.
Since the resistance to air flow will be less for horizontal duct connections than for bottom duct connections, add these pressures to the ESP values
on the respective unit’s blower performance table.
TABLE 16: POWER EXHAUST PERFORMANCE
MOTOR
SPEED
STATIC RESISTANCE OF RETURN DUCTWORK, IWG
0.2
0.3
0.4
0.5
0.6
CFM
KW
CFM
KW
CFM
KW
CFM
KW
CFM
KW
HIGH*
5250
0.83
4500
0.85
4200
0.88
3750
0.93
3000
0.99
MEDIUM
4900
0.77
3900
0.79
3500
0.82
2900
0.85
-
-
LOW
4400
0.72
3700
0.74
3000
0.78
-
-
-
-
TABLE 17: BLOWER MOTOR AND DRIVE DATA
MODEL
SIZE
DRIVE
BLOWER
RANGE
(RPM)
MOTOR
1
ADJUSTABLE MOTOR PULLEY
2
FIXED BLOWER PULLEY
BELT
(NOTCHED)
HP FRAME
EFF.
(%)
DESIG-
NATION
OUTSIDE
DIA.
(IN.)
PITCH
DIA.
(IN.)
BORE
(IN.)
DESIG-
NATION
OUTSIDE
DIA.
(IN.)
PITCH
DIA.
(IN.)
BORE
(IN.)
DESIG-
NATION
PITCH
LENGTH
(IN.)
QTY.
20 TON
Standard 870/1025
7.5 213 T
89
1VP68
6.75
5.5-6.5
1-3/8
BK120
11.75
11.4
1-3/16
BX83
84.8
1
High
Static
950/1120
BK110
10.75
10.4
1-3/16
BX80
81.8
1
1.
All motors have a nominal speed of 1800 RPM, a 1.15 service factor and a solid base. They can operate to the limit of their service factor because
they are located in the moving air, upstream of any heating device.
2.
Do NOT close this pulley below 1 turn open.
