JOHNSON CONTROLS
137
SECTION 7 – UNIT CONTROLS
FORM 150.72-ICOM7
ISSUE DATE: 10/22/2020
7
Option 18 – Pump Control
Pump Control is used to operate the optional onboard
pump kit or to control an external pump through dry
contacts 23 and 24 on Terminal Block XTBC2. To use
this option, the following selection should be made in
the Service Mode:
Y O R K H Y D R O
K I T P U M P S = 1
When YORK HYDRO KIT PUMPS = 1, the controls
will be closed to run the pumps whenever any one of
the following conditions are true:
• Low Leaving Chilled Liquid Fault
• Any compressor is running
• Daily Schedule is ON and Remote Stop is closed.
Even if one of the above conditions are
true, the pump will not run if the chiller
has been powered up for less than 30 sec-
onds; or if the pump has run in the last
30 seconds to prevent pump overheating.
E X T E R N A L
E V A P P U M P
EXTERNAL EVAP PUMP should be selected if an ex-
ternal pump is being controlled with the chiller pump
contacts. The operation will be the same as YORK
HDRO KIT PUMPS = 1
The following option should not be selected.
Y O R K H Y D R O
K I T P U M P S = 2
Option 19 – Pump Selection
The displays for this PUMP SELECTION option
should only appear if “YORK HYDRO KIT PUMPS =
2” are selected under Option 19. Presently, this option
should not be used.
Option 20 – Hot Gas Bypass Type
Hot gas bypass type cannot be programmed under the
options key. This option will display the hot gas by-
pass type as programmed in Service Mode for R-410A
units. Reference unloading logic flow chart for hot gas
bypass valve operation.
H O T G A S B Y P A S S T Y P E
N O N E
When programmed for hot gas bypass type None, the
unit will pump down and shutdown the lead system.
H O T G A S B Y P A S S T Y P E
S Y S T E M 1
When programmed for hot gas bypass type System 1,
the unit will operate system 1 hot gas bypass if system
1 is the lead system.
H O T G A S B Y P A S S T Y P E
S Y S T E M 2
When programmed for hot gas bypass type System 2,
the unit will operate system 2 hot gas bypass if system
2 is the lead system.
H O T G A S B Y P A S S T Y P E
B O T H S Y S T E M S
When programmed for hot gas bypass type Both Sys-
tems, the condensing units operating in suction pres-
sure control operate independent of the lead/lag sys-
tem. All other units will use the hot gas bypass valve of
the lead system when unloading.
Option 21 – Flash Card Data Logging
When the following message appears, data logging is
disabled.
D A T A L O G T O F L A S H C A R D
O F F
When the following message appears, data logging is
enabled.
D A T A L O G T O F L A S H C A R D
O N
When the following message appears, data logging is
enabled and is not logging unchanged data.
D A T A L O G T O F L A S H C A R D
S K I P U N C H A N G E D
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