Unit installation

APPENDIX
Troubleshooter's guide
SYMPTOMS POSSIBLE CAUSE CORRECTIVE ACTION
10. Suction pressure too high
Insufficient compression - defective
compressor.
Check compressor for internal damage,
repair/ replace compressor.
Overfeeding of expansion valve. Check superheat setting, and take suitable
corrective action.
Expansion valve stuck open. Repair/ replace valve.
High discharge pressures. Refer section 8 in this guide and take
corrective action.
11.Suction pressure too low. Shortage of refrigerant. Repair leak and recharge.
Possible Controller message:
Wrong expansion valve superheat setting. Adjust superheat setting.
Dirty or defective expansion valve. Clean/ repair/ replace expansion Valve.
Reduced cooler performance (cooler tubes
fouled retarding heat transfer).
Check cooler efficiency and clean water
side of cooler.
12. Compressor is noisy. Improper compressor mounting. Repair/ replace compressor mounts.
Liquid flooding back to compressor. Refer section 13 in this guide and take
corrective action.
Oil slugging or excessive oil in system. Remove excess oil from the system.
Compressor internal parts broken or worn
out.
Repair/ replace compressor.
Insufficient lubrication. Check oil level & condition and take
corrective action.
13. Suction line sweating
excessively or frosted.
Wrong expansion valve superheating
setting.
Adjust superheat setting.
Expansion valve stuck open. Repair/ replace expansion valve
Refrigerant overcharge Remove/ purge the excess refrigerant
charge.
Liquid line solenoid valve stuck open or
held open manually.
Repair/ replace valve or restore to
automatic operation.
Clogged filter drier Replace drier elements/cores.
Liquid line shut off valve partially closed. Open valve fully.
b. Liquid line solenoid valve
hisses when closed. Also,
temperature change in refrigerant
line through valve.
Leaking liquid line solenoid valve Repair/ replace valve.
Faulty wiring or loose connections. Repair wiring or connections.
Bad fan motor bearings. Replace bearings or motor.
Burntout fan motor. Replace fan motor.
16. a. No LED/ LCD display on
controllor or erratic display
behaviour.
Problem with serial cable integrity,
connections or controller malfunction.
Refer section on "Microprocessor controller"
in this manual and take suitable corrective
action.
b. Controller does not respond to
keypad.
Jumper and/or dip switch wrong
configuration
Check jumper and/or dip switch (refer to
respective wiring diagram).
c. Auxilary board not responding to
commands
d. Analog outputs or digital outputs
not responding.
Possible controller message:
ALARM COMPRESSOR N.X
SERIAL COMMUNICATION.
14. a. Liquid line sweating or
frosted.
15. Condenser fan motor does not
run.
ALARM COMPRESSOR N.#
SUCTION PRES. LOW.
(liquid refrigerant flooding
compressor)
Study the load profile/ demand carefully and
take corrective action.
Excessive load or chiller is undersized.
Low load on cooler (water temp. low or
reduced water flow).
Locate cause and take corrective action.
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