Stulz CyberWall CAH - Field Service

30 11.8.22 © STULZ USA – all rights reserved
CYBERWALL™ INSTALLATION, OPERATION AND MAINTENANCE MANUAL
Table 1. Troubleshooting Procedures
SYMPTOM PROBABLE CAUSE RECOMMENDATION
Chilled Water Valve Fails
to Open or Close
a. Temperature set point too high/low. Adjust to correct temperature setting.
b. No control power to chilled water
valve.
Check wiring and rewire if required.
c. Actuator failed. Replace actuator
Fan(s) fail to start (AC
induction models)
a. Power failure. Check main power source and/or
input power cable/wiring.
b. Motor starter protector (MSP)
tripped.
Reset MSP and check amperage of
motor. Compare to setting on
MSP and adjust to correct FLA if
necessary.
c. Control transformer circuit tripped. Check for short circuit or ground fault.
If none, reset circuit breaker.
Fan(s) fail to start (EC
models)
a. Power failure. Check main power source and/or
input power cable/wiring.
b. Motor starter protector (MSP)
tripped.
Reset MSP and check amperage
of motor. Compare to setting on
MSP and adjust to correct FLA if
necessary.
c. Control transformer circuit tripped. Check for short circuit or ground fault.
If none, reset circuit breaker.
Control is erratic Wiring improperly connected or
broken.
Check wiring against schematic
diagram.
System performance less
than capacity
a. Low CW flow Check for leaks or partially closed
valve.
b. Supply water temperature too high. Check CW supply temperature.
c. Reduced air flow. Check fan filter grilles and clean as
required.
d. Dirty coil. Clear coil fins of dirt and debris.
Field Service
NOTE
Do not attempt to make repairs without the proper tools.
It may be necessary to perform repairs on the A/C system. If field repairs are necessary, the following
procedures apply: