York YLAA Series Installation Operation & Maintenance page 6

SECTION 6 - COMMISSIONING ............................................................................................................................99
Preparation - Power Off ................................................................................................................................. 99
Preparation - Power On ............................................................................................................................... 101
How to Commission the Pump VFD ............................................................................................................. 102
SECTION 7 - UNIT CONTROLS ..........................................................................................................................107
Introduction ................................................................................................................................................... 107
IPU II and I/O Boards ................................................................................................................................... 107
Transformer ................................................................................................................................................. 108
Display .......................................................................................................................................................... 108
Keypad ......................................................................................................................................................... 108
Unit Switch ................................................................................................................................................... 108
Battery Back-Up ........................................................................................................................................... 108
Programming # oOf Compressors ................................................................................................................ 108
Status Key .................................................................................................................................................... 109
Display/Print Keys ........................................................................................................................................ 115
Entry Keys .................................................................................................................................................... 123
Setpoints Keys ............................................................................................................................................. 124
Schedule/Advance Day Key ......................................................................................................................... 125
Program Key ................................................................................................................................................ 127
Unit Keys ..................................................................................................................................................... 131
Bacnet, Modbus, N2 and Yorktalk 2 Communications ................................................................................. 137
SECTION 8 - UNIT OPERATION .........................................................................................................................149
Capacity Control ........................................................................................................................................... 149
Suction Pressure Limit Controls ................................................................................................................... 150
Discharge Pressure Limit Controls ............................................................................................................... 150
Leaving Chilled Liquid Control ...................................................................................................................... 150
Leaving Chilled Liquid Control Override to Reduce Cycling ......................................................................... 151
Leaving Chilled Liquid System Lead/Lag and Compressor Sequencing ...................................................... 152
Return Chilled Liquid Control ....................................................................................................................... 152
Return Chilled Liquid System Lead/Lag and Compressor Sequencing ....................................................... 153
Anti-Recycle Timer ....................................................................................................................................... 153
Anti-Coincidence Timer ................................................................................................................................ 153
Evaporator Pump Control and York Hydro Kit Pump Control ....................................................................... 153
Evaporator Heater Control ........................................................................................................................... 154
Pumpdown Control ....................................................................................................................................... 154
Standard Condenser Fan Control ................................................................................................................ 154
Load Limiting ................................................................................................................................................ 158
Compressor Run Status ............................................................................................................................... 158
Alarm Status ................................................................................................................................................. 158
Remote BAS/EMS Temperature Reset Using a Voltage or Current Signal .................................................. 159
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TABLE OF CONTENTS (CONT'D)
FORM 150.72-ICOM6
ISSUE DATE: 12/29/2017
JOHNSON CONTROLS