York YLAA0285SE Manual page 8

SECTION 8 - UNIT OPERATION .................................................................................................................167
CAPACITY CONTROL ............................................................................................................................167
SUCTION PRESSURE LIMIT CONTROLS ...........................................................................................167
DISCHARGE PRESSURE LIMIT CONTROLS .....................................................................................167
LEAVING CHILLED LIQUID CONTROL ...............................................................................................167
LEAVING CHILLED LIQUID SYSTEM LEAD/LAG AND COMPRESSOR SEQUENCING ..............168
LEAVING CHILLED LIQUID CONTROLOVERRIDE TO REDUCE CYCLING ..................................168
RETURN CHILLED LIQUID CONTROL ................................................................................................169
RETURN CHILLLED LIQUID SYSTEM LEAD/LAG AND COMPRESSOR SEQUENCING .............170
ANTI-RECYCLE TIMER ..........................................................................................................................171
ANTI-COINCIDENCE TIMER ..................................................................................................................171
EVAPORATOR PUMP CONTROL & YORK ..........................................................................................171
HYDRO KIT PUMP CONTROL ...............................................................................................................171
EVAPORATOR HEATER CONTROL .....................................................................................................171
PUMPDOWN CONTROL .........................................................................................................................171
STANDARD CONDENSER FAN CONTROL .........................................................................................171
LOAD LIMITING .......................................................................................................................................175
COMPRESSOR RUN STATUS ...............................................................................................................175
ALARM STATUS ......................................................................................................................................175
BAS/EMS TEMPERATURE RESET USINGA VOLTAGE OR CURRENT SIGNAL ...........................176
SECTION 9 - SERVICE AND TROUBLESHOOTING ................................................................................177
CLEARING HISTORY BUFFERS ...........................................................................................................177
SERVICE MODE ......................................................................................................................................177
SERVICE MODE - OUTPUTS ................................................................................................................177
SERVICE MODE - CHILLER CONFIGURATION .................................................................................178
SERVICE MODE - ANALOG & DIGITAL INPUTS ...............................................................................178
CONTROL INPUTS/OUTPUTS ..............................................................................................................179
MICROBOARD LAYOUT ........................................................................................................................180
CHECKING INPUTS AND OUTPUTS ....................................................................................................181
Digital Inputs ......................................................................................................................................181
Analog Inputs - Temperature ...........................................................................................................181
Outside Air Sensor ............................................................................................................................181
Liquid & Refrigerant Sensor Test Points ........................................................................................182
Analog Inputs - Pressure .................................................................................................................183
Digital Outputs ...................................................................................................................................184
OPTIONAL PRINTER INSTALLATION .................................................................................................185
Parts ....................................................................................................................................................185
Assembly and Wiring ........................................................................................................................185
Obtaining a Printout ..........................................................................................................................185
TROUBLESHOOTING .............................................................................................................................186
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TABLE OF CONTENTS (CONT'D)
FORM 150.72-NM3 (1020)
ISSUE DATE 10/05/2020
JOHNSON CONTROLS