5565606-TIM-B-1018
52
Johnson Controls Ducted Systems
Operation
Cooling Sequence Of Operation
NOTE:
For more in-depth sequence of operation of the Smart
Equipment™ control, refer to the
Smart Equipment™
Controls Sequence of Operation Overview
LIT-
12011950 available from your equipment dealer or
distributor.
For ZW units, a "Y1" call for the first stage of cooling is passed
to the Unit Control Board (UCB) which then determines whether
the requested operation is available and if so, which
components to energize. With a "Y1" call for first stage cooling
the UCB will determine if a first stage cooling output is valid as
long as all safeties and time-delays allow a C1 output for
cooling. The C1 relay on the UCB will close and send 24 volts
to the M1 contactor starting the first stage compressor and the
associated condenser fan.
If a Y2 call is present it is passed to the Unit Control Board
(UCB) which then determines whether the requested operation
is available and if so, which components to energize. With a
"Y2" call for first stage cooling the UCB will determine if a
second stage cooling output is valid as long as all safeties and
time-delays allow a C2 output for cooling. The C2 relay on the
UCB will close and send 24 volts to the M2 contactor starting
the first stage compressor and the associated condenser fan.
Continuous Blower
By setting the room thermostat fan switch to "ON," the supply
air blower will operate continuously.
Intermittent Blower
With the room thermostat fan switch set to "AUTO" and the
system switch set to either the "AUTO" or "HEAT" settings, the
blower is energized whenever a cooling or heating operation is
requested. The blower is energized after any specified delay
associated with the operation.
When energized, the indoor blower has a minimum run time of
30 seconds. Additionally, the indoor blower has a delay of 10
seconds minimum off.
Table 23: Additional Static Resistance
Size
(Tons)
Model
CFM
Cooling Only
1
1. Add these values to the available static resistance in the respective Blower Performance Tables.
Economizer
2
,
3
2. Deduct these values from the available external static pressure shown in the respective Blower Performance Tables.
3. The pressure drop through the economizer is greater for 100% outdoor air than for 100% return air. If the resistance of the return air duct is
less than 0.25 IWG, the unit will deliver less CFM during full economizer operation.
4” Filter
2
Electric Heat kW
9
18
24
36
54
T06 (6.5)
T07 (7.5)
T08 (8.5)
T10 (10)
T12 (12.5)
ZW
1900
0.06
0.02
0.12
0.05
0.06
0.07
0.08
0.10
2100
0.07
0.02
0.13
0.06
0.07
0.08
0.09
0.11
2300
0.08
0.04
0.14
0.07
0.08
0.09
0.10
0.13
2500
0.09
0.11
0.16
0.08
0.09
0.10
0.11
0.14
2700
0.11
0.18
0.17
0.09
0.10
0.12
0.13
0.16
2900
0.12
0.25
0.19
0.10
0.11
0.13
0.14
0.18
3100
0.14
0.31
0.20
0.12
0.13
0.15
0.16
0.20
3300
0.16
0.37
0.22
0.13
0.14
0.17
0.18
0.22
3500
0.18
0.43
0.26
0.15
0.16
0.19
0.20
0.24
3700
0.20
0.49
0.27
0.17
0.18
0.21
0.22
0.26
3900
0.23
0.54
0.29
0.19
0.20
0.23
0.24
0.28
4100
0.25
0.58
0.32
0.21
0.22
0.25
0.26
0.31
4300
0.28
0.65
0.35
0.23
0.24
0.28
0.29
0.34
4500
0.30
0.69
0.38
0.25
0.26
0.30
0.31
0.37
4700
0.33
0.74
0.41
0.28
0.29
0.33
0.34
0.40
4900
0.36
0.78
0.44
0.30
0.31
0.35
0.37
0.43
5100
0.39
0.82
0.47
0.33
0.34
0.38
0.40
0.46
5300
0.42
0.86
0.51
0.35
0.37
0.41
0.43
0.49
5500
0.45
0.89
0.55
0.38
0.40
0.44
0.46
0.53
5700
0.48
0.93
0.58
0.41
0.43
0.47
0.49
0.56
5900
0.52
0.96
0.62
0.44
0.46
0.50
0.53
0.59
6100
0.56
0.98
0.67
0.47
0.49
0.53
0.56
0.62
6300
0.60
1.01
0.71
0.50
0.53
0.56
0.59
0.65
