(© Aug, 2006)
Compact CWE Series Installation, Operation & Maintenance Manual
4-2
SYMPTOM PROBABLE CAUSE RECOMMENDATION
4.2 Troubleshooting
WARNING
Turn off all power to the unit before conducting any troubleshooting procedures, unless the procedure specifi-
cally requires the system to operate. For troubleshooting purposes, the system may be operated with the
doors open by using a pair of channel lock pliers to turn the shaft of the main power disconnect switch to the
“on” position. When the switch is turned on, high voltage will be present inside the cabinet. Exercise caution
to prevent injury. Keep hands, clothing and tools clear of the electrical terminals and rotating components.
Ensure that your footing is stable at all times.
Chilled Water Valve Fails a. Temperature setpoint too high. Adjust to correct temperature setting.
to Open or Close
b. No control power to the valve. Valve actuator is wired incorrectly.
Check wiring schematic and rewire if
required.
c. Actuator failed. Replace actuator.
EC Fan(s) Fail to Start a. Power failure. Check main voltage power source
input cable.
b. Motor starter protector tripped. Reset motor starter protector and check
amperage of motor. Compare to setting
on motor circuit controller and adjust to
FLA.
c. Control transformer circuit Check for short circuit or ground fault,
breaker tripped. if none reset circuit breaker.
d. Defective contactor. Repair or replace.
e. No control signal to fan(s). Check the Control I/O Board for a 0-10
VDC control signal to the fan(s). Refer
to the electric drawing to determine the
correct I/O board terminal numbers. (This
must done within 15 seconds of turning
the disconnect switch on or the controller
will go into “Air Proving Alarm” mode.
Control is Erratic Wiring improperly connected or Check wiring against schematic
broken. diagram.
System Short of Capacity a. Low Chilled Water flow Check for leaks Repair and recharge
system.
b. Supply water temperature too high Check chilled water supply
c. Reduced airflow. Check filters
To Next Page
Loading...
