7.4 Control and protection function of unit
7.4.1 The unit has the following protection functions
1) Current cut-off protection
2) Power supply phase sequence protection
3) Protection for over-low suction pressure
4) Protection for compressor overcurrent
5) Protection for compressor overload
6) Anti-freezing protection
7) Protection for over-high discharge pressure
8) Protection for outlet and inlet water temperature
difference
7.4.2 The unit also has other control functions:
1) Manual test function
2) Plug and play system
3) RS-485/RS232 Standard serial communication port.
7.5 Troubleshooting
Table 7-1
Error
Possible reason
Air or other non-condensing gas still
in the system
Detect and settle measure
Discharge gas from fluorin charging inlet. Re-vacuum the system if
necessary.
Air or other non-condensing gas still
in the system
Discharge gas from fluorin charging inlet. Re-vacuum the system if
necessary.
Fins in the condenser are dirty or
foreign substance blocking fins.
Insufficient chilling air volume or
condenser fan error
Excessive high air suction pressure
Excessive refrigerant charging volume
Over high ambient temperature
See “Excessive high air suction pressure”
Discharge the excessive refrigerant
Excessive refrigerant charging volume
Over high temperature in chilling water inlet
Insufficient water flow volume
Incrustant in evaporator
Insufficient water flow
Incrustant in water side of heat exchanger
Over high temperature in chilling water inlet
Excessive high air suction pressure
Over low temperature of chilling water
Excessive low air suction pressure
Excessive refrigerant charging volume
Insufficient refrigerant charging volume
Insufficient air flow volume
Air loop short-circuit
Over heat air in the side of air heat exchanger
Refrigerant leakage or insufficient
refrigerant volume
Over low temperature in chilling water
inlet and outlet
Discharge the excessive refrigerant
Check and installation state
Test leakage or charge sufficient refrigerant to the system
Eliminate incrustant
Eliminate incrustant
Check water temperature
See “Excessive high air suction pressure”
Check chilling water temperature
Refrigerant leakage or insufficient
refrigerant volume
Test leakage or charge sufficient refrigerant to the system
See “Excessive low air suction pressure”
Check ambient temperature around it
Discharge the excessive refrigerant
Charge sufficient refrigerant to the system
Check fan rotating direction
Reason about remove air short-circuit
Insufficient frost-removal operation
Error comes out from 4-way valve or thermal resistor. Replace a new one if necessary.
Check temperature difference at water inlet and outlet, and adjust the
water flow volume
Check temperature difference at water inlet and outlet, and adjust the
water flow volume
Check thermal insulation layer of water pipe and the specification of this layer
Check ambient temperature
Over cool air in the side of air heat
exchanger
Refrigerant leakage or insufficient r
efrigerant volume
Excessive low air suction pressure
Check ambient temperature
Test leakage or charge sufficient refrigerant to the system
See “Excessive low air suction pressure”
Check and repair the condenser fan, recover the normal operation
Clean condenser fins.
Insufficient chilling water flow volume
Gas still in water loop
Error comes from pump or flow-type water volume control. Check and
repair or replace a new one.
Discharge air
Thermal resistor error
Over high air expelling pressure
Upon error have been confirmed, please replace a new one.
See “Over high air expelling pressure”
Hi-pressure switch error
Upon error have been confirmed, please replace a new one.
Over high air
discharge pressure
(Cooling operation)
Over low air
discharge pressure
(Cooling operation)
Over low air
suction pressure
(Cooling operation)
Over high air
discharge pressure
(Heating operation)
Over low air
discharge pressure
(Heating operation)
Over low air
suction pressure
(Heating operation)
Compressor stops
because of freeze-proof
protection (Cooling
operation)
Compressor stops because
of Hi-pressure protection
Over high air
suction pressure
(Heating operation)
Over high air
suction pressure
(Cooling operation)
Network ON
ć
A
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O&I manual
20
Summary of Contents for ICHS-420KC-5
Page 33: ......
