335224-BIM-B-1208
48
Johnson Controls Unitary Products
OPERATION
SEQUENCE OF OPERATIONS OVERVIEW
For the Predator MagnaDRY™ series of units, the thermostat
makes a circuit between "R" and "Y1" for the first stage of
cooling.
The call is passed to the
Unit Control Board (UCB)
, which
then determines whether the requested operation is available
and, if so, which components to energize.
For gas heating, the UCB monitors the "W1" call but does not
handle the operation of the gas furnace. An ignition control
board controls the gas heater operation. For electric heat
units, the UCB passes the call to the electric heater. In both
cases, when the "W1" call is sensed, the indoor air blower is
energized following a specified heating delay.
If at any time a call for both heating and cooling are present,
the heating operation will be performed. If operating, the cool-
ing system is halted as with a completion of a call for cooling.
Heating always takes priority.
TABLE 33: ADDITIONAL STATIC RESISTANCE
CFM
Gas Heat
Electric Heat KW
9
18
24
36
54
2300
0.08
0.07
0.08
0.09
0.10
0.13
2500
0.09
0.08
0.09
0.10
0.11
0.14
2700
0.11
0.09
0.10
0.12
0.13
0.16
2900
0.12
0.10
0.11
0.13
0.14
0.18
3100
0.14
0.12
0.13
0.15
0.16
0.20
3300
0.16
0.13
0.14
0.17
0.18
0.22
3500
0.18
0.15
0.16
0.19
0.20
0.24
3700
0.20
0.17
0.18
0.21
0.22
0.26
3900
0.23
0.19
0.20
0.23
0.24
0.28
4100
0.25
0.21
0.22
0.25
0.26
0.31
4300
0.28
0.23
0.24
0.28
0.29
0.34
4500
0.30
0.25
0.26
0.30
0.31
0.37
4700
0.33
0.28
0.29
0.33
0.34
0.40
4900
0.36
0.30
0.31
0.35
0.37
0.43
5100
0.39
0.33
0.34
0.38
0.40
0.46
5300
0.42
0.35
0.37
0.41
0.43
0.49
5500
0.45
0.38
0.40
0.44
0.46
0.53
5700
0.48
0.41
0.43
0.47
0.49
0.56
5900
0.52
0.44
0.46
0.50
0.53
0.59
6100
0.56
0.47
0.49
0.53
0.56
0.62
6300
0.60
0.50
0.53
0.56
0.59
0.65
TABLE 34: MOTOR SHEAVE DATUM DIAMETERS
1VM50x7/8
(1-1/2, 2 & 3 HP Motor)
1VP56x1-1/8
(5 HP Motor)
Turns Open
Datum
Diameter
Turns Open
Datum
Diameter
0
4.4
1
5.3
1/2
4.3
1-1/2
5.2
1
4.2
2
5.1
1-1/2
4.1
2-1/2
5.0
2
4.0
3
4.9
2-1/2
3.9
3-1/2
4.8
3
3.8
4
4.7
3-1/2
3.7
4-1/2
4.6
4
3.6
5
4.5
4-1/2
3.5
5-1/2
4.4
5
3.4
6
4.3
