5464597-YIM-B-0518
Johnson Controls Ducted Systems
53
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 ZF 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 relay starting the first stage compressor and also
energizing the associated condenser fans. During any call for
fan or cooling the FAN output on the UCB will energize the M3
relay starting the supply 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
Table 22: 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
078 (6.5)
090 (7.5)
ZF
1900
0.00
0.07
0.10
0.05
0.06
0.07
0.08
0.10
2100
-0.01
0.09
0.11
0.06
0.07
0.08
0.09
0.11
2300
-0.01
0.11
0.12
0.07
0.08
0.09
0.10
0.13
2500
-0.02
0.13
0.14
0.08
0.09
0.10
0.11
0.14
2700
-0.03
0.16
0.15
0.09
0.10
0.12
0.13
0.16
2900
-0.04
0.18
0.16
0.10
0.11
0.13
0.14
0.18
3100
-0.05
0.20
0.18
0.12
0.13
0.15
0.16
0.20
3300
-0.06
0.22
0.19
0.13
0.14
0.17
0.18
0.22
3500
-0.07
0.24
0.20
0.15
0.16
0.19
0.20
0.24
3700
-0.08
0.27
0.21
0.17
0.18
0.21
0.22
0.26
3900
-0.09
0.29
0.23
0.19
0.20
0.23
0.24
0.28
4100
-0.09
0.31
0.24
0.21
0.22
0.25
0.26
0.31
4300
-0.10
0.30
0.25
0.23
0.24
0.28
0.29
0.34
4500
-0.11
0.35
0.26
0.25
0.26
0.30
0.31
0.37
102 (8.5)
120 (10)
150 (12.5)
ZF
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