Multistack MS030XC - Troubleshooting Guide

37
Fault Solution Fault Solution
No Display on Master Module
• Check main disconnect for power
• Check circuit breakers in module
• Check transformer in modules
• Check for 24V at J1 on board
100% Demand,
chiller won’t load
• Turn chiller on
• Check sensors
• Check load limit setting in system variables
Excessive Cycling
• Check VSP setting is system variables
• Check entering CHW sensor location
• Look for system problem (low water Volume,
low load)
EX 1,2, Interlock
• Check appropriate interlock component
• Check jumpers on TB11 in master control
EX 4 Interlock
• Check for proper rotation, phasing
• Check PPM device
High Discharge Pressure (HP)
• Check strainers in condenser headers
• Check condenser water ow
Waiting For Chilled Water Flow
• Check CHW pump
• Check ow switch operation
• Check lter strainers
• Check TB11 inputs #3 - #7
Low Suction Pressure (LP)
• Check refrigerant charge / leaks
• Check expansion valve
Low Suction Temperature
• Check suction sensor
• Check set-points in system variables
• Check for ow restriction
Waiting For Condenser
Water Flow
• Check CW pump
• Check ow switch operation
• Check lter strainers
• Check TB11 inputs #3 - #8
Communication Error
• Check settings in system variables
• Check cables at J11 comm ports
• Check dip switch settings
Low Chilled Water Temp
• Check LCHW sensor
• Check set-points in system variables
• Check for ow restriction
Circuit Fault
• Check components in control circuit
• Check wire crimps in control circuit
• Check ratio of HP to LP
No Demand
• Check entering CHW sensor
• Check set-points in system variables
• Check sensor location
P Lan Error
• Check cables at J11 comm ports
• Check for possible power issues
100% Demand all the time
• Check entering CHW sensor
• Check set-points in system
variables
Troubleshooting
Multistack modular chillers use the Carel PCO3 master control. A user manual for the PCO3 controller is supplied with the submittal package. The user
manual details the dierent status screens and explanations of system or module faults. Use the following guide to troubleshoot modules and the PC03
controller.