Kaysun KEM-30 DRS4 User manual

SERVICE MANUAL
DC Inverter Air-cooled Modular Chiller
KEM-30 DRS4
KEM-60 DRS4
KEM-30 DRS4 KH
KEM-60 DRS4 KH

1
CONTENTS
Part 1 General Information ........................................................................... 3
Part 2 Component Layout and Refrigerant Circuits......................................... 5
Part 3 Control .............................................................................................. 23
Part 4 Diagnosis and Troubleshooting.......................................................... 39
CONTENTS

2

3
Part 1 - General Information
Part 1
General Information
1 Unit Capacities and External Appearance ..............................................4
2 Water outlet temperature range ...........................................................4

4
1 Unit Capacities and External Appearance
Table 1-1.1: Aqua Tempo Super II unit capacity range and unit appearances
Capacity 30kW 60kW
Model KEM-30 DRS4
KEM-30 DRS4 KH
KEM-60 DRS4
KEM-60 DRS4 KH
Appearance
Power
supply 380-415V/3Ph/50Hz
2 Water outlet temperature range
Table 1-2.1: Aqua Tempo Super II unit water outlet temperature range
Mode Range
Cooling Normal 5-20°C1
Low water outlet 0-20°C(reserved)2
Heating Normal 25-54°C
Notes:
1. For 30kW and 60kW units, when the ambient temperature is below 15°C, the water outlet temperature range is 10-20°C. When the ambient temperature
is above 15°C,all the units water outlet temperature range is 5-20°C.
2. For 30kW and 60kW units, use dial switch S12_3 on the main PCB to select the water outlet temperature range.

5
Part 2 - Component Layout and Refrigerant Circuits
Part 2
Component Layout and
Refrigerant Circuits
1 Layout of Functional Components .........................................................6
2 Piping Diagrams .................................................................................. 14
3 Refrigerant Flow Diagrams ................................................................. 20

6
1 Layout of Functional Components
KEM-30 DRS4
Figure 2-1.1: KEM-30 DRS4 front view
Wired
controller Electric
control box
Oil separator
Fan motor
DC inverter
compressor
Manual air
purge valve
Manual water
drain valve
Water outlet
pipe
Water side heat exchanger
Safety valve
Water flow switch
Water inlet pipe
Accumulator
Figure 2-1.2: KEM-30 DRS4 rear view

7
Part 2 - Component Layout and Refrigerant Circuits
Figure 2-1.3: KEM-30 DRS4 top view
Low pressure
switch
Electronic
expansion valve
High pressure
switch
High pressure
sensor
Four-way valve
Accumulator
Solenoid valve
SV4
Discharge
temperature
switch
Low pressure
gauge point
High pressure
gauge point

8
KEM-30 DRS4 KH
Figure 2-1.4: KEM-30 DRS4 KH front view
Wired
controller Electric
control box
DC inverter
compressor
Water side heat
exchanger
Manual water
drain valve
Manual air
purge valve
Safty valve
Water outlet pipe
Water flow switch
Buffer
Water inlet pipe
Accumulator
Fan motor
Oil separator
Figure 2-1.5: KEM-30 DRS4 KH rear view

9
Part 2 - Component Layout and Refrigerant Circuits
Low pressure
switch
Solenoid valve
SV4
Discharge
temperature
switch
Low pressure
gauge point
High pressure
gauge point
Electronic
expansion valve
High pressure
sensor
High pressure
switch
Accumulator
Four-way valve
Figure 2-1.6: KEM-30 DRS4 KH top view

10
Figure 2-1.8: KEM-60 DRS4 rear view
KEM-60 DRS4
Figure 2-1.7: KEM-60 DRS4 front view
DC inverter
compressor
Electric
control box
Fan motor
Oil separator
Safety valve
Air purge valve
Water inlet pipe
Manual water
drain valve
Water outlet
pipe
Accumulator
Accumulator
Water side heat
exchanger
Water flow
switch

11
Part 2 - Component Layout and Refrigerant Circuits
Figure 2-1.9: KEM-60 DRS4 top view
Low pressure
switch
High pressure
sensor
High pressure
switch
Four-way valve
Electronic
expansion valve
Solenoid
valve SV4
Discharge
temperature
switch
Low pressure
gauge point
High pressure
gauge point

12
Figure 2-1.11: KEM-60 DRS4 KH rear view
KEM-60 DRS4 KH
Figure 2-1.10: KEM-60 DRS4 KH front view
DC inverter
compressor
Electric
control box
Fan motor
Oil separator
Safety valve
Air purge valve
Water inlet pipe
Water flow switch
Water outlet pipe
Manual wate
drain valve
Accumulator
Accumulator
Accumulator
Water side heat
exchanger
Buffer

13
Part 2 - Component Layout and Refrigerant Circuits
Figure 2-1.12: KEM-60 DRS4 KH top view
Low pressure
switch
High pressure
sensor
High pressure
switch
Four-way valve
Electronic
expansion valve
Solenoid
valve SV4
Discharge
temperature
switch
Low pressure
gauge point
High pressure
gauge point

14
2 Piping Diagrams
KEM-30 DRS4
Figure 2-2.1: KEM-30 DRS4 piping diagram
inlet
outlet
Legend
1 DC inverter compressor 22 Stop valve
2 Crankcase heater 23 Safety valve
3 DC inverter compressor discharge temperature sensor 1 24 Vapor-liquid separator
4 DC inverter compressor discharge temperature sensor 2 25 Suction temperature sensor
5 Discharge temperature control switch 26 Filter
6 High pressure switch 27 Capillary
7 Oil separator 28 Fast oil return solenoid valve
8 4-way-valve 29 Low pressure switch
9 System pressure sensor 30 Filter
10 DC fan 31 Capillary
11 Condenser 32 Outdoor ambient temperature sensor
12 Coil outlet temperature sensor 33 Unit water inlet temperature sensor
13 Coil final outlet temperature sensor 34 Safety valve
14 Filter 35 Air purge valve
15 Electronic expansion valve 36 Unit water outlet temperature sensor
16 Filter 37 Water flow switch
17 High pressure tank 38 Manual water drain valve
18 Antifreeze heater of plater heat exchanger 39 Total outlet water temperature sensor
19 Water side antifreeze temperature sensor 2 40 Plate heat exchanger
20 Water side antifreeze temperature sensor 1 41 Capillary
21 Stop valve 42 Liquid injection solenoid valve

15
Part 2 - Component Layout and Refrigerant Circuits
KEM-30 DRS4 KH
Figure 2-2.2: KEM-30 DRS4 KH piping diagram
Legend
1 DC inverter compressor 23 Safety valve
2 Crankcase heater 24 Vapor-liquid separator
3 DC inverter compressor discharge temperature sensor 1 25 Suction temperature sensor
4 DC inverter compressor discharge temperature sensor 2 26 Filter
5 Discharge temperature control switch 27 Capillary
6 High pressure switch 28 Fast oil return solenoid valve
7 Oil separator 29 Low pressure switch
8 4-way-valve 30 Filter
9 System pressure sensor 31 Capillary
10 DC fan 32 Outdoor ambient temperature sensor
11 Condenser 33 Unit water inlet temperature sensor
12 Coil outlet temperature sensor 34 Safety valve
13 Coil final outlet temperature sensor 35 Air purge valve
14 Filter 36 Unit water outlet temperature sensor
15 Electronic expansion valve 37 Water flow switch
16 Filter 38 Manual water drain valve
17 High pressure tank 39 Total outlet water temperature sensor
18 Antifreeze heater of plater heat exchanger 40 Plate heat exchanger
19 Water side antifreeze temperature sensor 2 41 Capillary
20 Water side antifreeze temperature sensor 1 42 Liquid injection solenoid valve
21 Stop valve 43 Expansion tank
22 Stop valve 44 Pump
inlet
outlet

16
KEM-60 DRS4
Figure 2-2.3: KEM-60 DRS4 piping diagram
inlet
outlet
Legend
1 DC inverter compressor 1 26 Antifreeze heater of plate heat exchanger
2 DC inverter compressor 2 27 Water side antifreeze temperature sensor 2
3 Crankcase heater 1 28 Water side antifreeze temperature sensor 1
4 Crankcase heater 2 29 Stop valve
5 DC inverter compressor discharge temperature sensor 1 30 Stop valve
6 DC inverter compressor discharge temperature sensor 2 31 Safety valve
7 Discharge temperature control switch 1 32 Vapor-liquid separator
8 Discharge temperature control switch 2 33 Suction temperature sensor
9 One-way valve 1 34 Low pressure switch
10 One-way valve 2 35 Filter
11 High pressure switch 36 Capillary
12 Oil separator 37 Fast oil return solenoid valve
13 4-way valve 38 Filter
14 System pressure sensor 39 Capillary
15 DC fan 1 40 Outdoor ambient temperature sensor
16 DC fan 2 41 Unit water inlet temperature sensor
17 Condenser 42 Safety valve
18 Coil outlet temperature sensor 43 Air purge valve
19 Coil final outlet temperature sensor 44 Unit water outlet temperature sensor
20 Filter 45 Water flow switch
21 Electronic expansion valve 46 Total outlet water temperature sensor
22 One-way valve 3 47 Manual water drain valve
23 Capillary 48 Plater exchanger
24 Filter 49 Capillary
25 High pressure tank 50 Liquid injection solenoid valve

17
Part 2 - Component Layout and Refrigerant Circuits
KEM-60 DRS4 KH
Figure 2-2.4: KEM-60 DRS4 KH piping diagram
Legend
1 DC inverter compressor 1 27 Water side antifreeze temperature sensor 2
2 DC inverter compressor 2 28 Water side antifreeze temperature sensor 1
3 Crankcase heater 1 29 Stop valve
4 Crankcase heater 2 30 Stop valve
5 DC inverter compressor discharge temperature sensor 1 31 Safety valve
6 DC inverter compressor discharge temperature sensor 2 32 Vapor-liquid separator
7 Discharge temperature control switch 1 33 Suction temperature sensor
8 Discharge temperature control switch 2 34 Low pressure switch
9 One-way valve 1 35 Filter
10 One-way valve 2 36 Capillary
11 High pressure switch 37 Fast oil return solenoid valve
12 Oil separator 38 Filter
13 4-way valve 39 Capillary
14 System pressure sensor 40 Outdoor ambient temperature sensor
15 DC fan 1 41 Unit water inlet temperature sensor
16 DC fan 2 42 Safety valve
17 Condenser 43 Air purge valve
18 Coil outlet temperature sensor 44 Unit water outlet temperature sensor
19 Coil final outlet temperature sensor 45 Water flow switch
20 Filter 46 Total outlet water temperature sensor
21 Electronic expansion valve 47 Manual water drain valve
22 One-way valve 3 48 Plater exchanger
23 Capillary 49 Capillary
24 Filter 50 Liquid injection solenoid valve
25 High pressure tank 51 Expansion tank
26 Antifreeze heater of plate heat exchanger 52 Pump
inlet
outlet

18
Key components:
1. Compressor
Maintains pressure differential between high and low pressure sides of the refrigerant system.
2. Fan:
Ventilates the air side heat exchanger.
3. Oil separator:
Separates oil from gas refrigerant pumped out of the compressor and quickly returns it to the compressor. Separation
efficiency is up to 99%.
4. Accumulator:
Stores liquid refrigerant and oil to protect the compressor from liquid hammering.
5. Electronic expansion valve (EXVA/B/C):
Controls refrigerant flow and reduces refrigerant pressure.
6. Four-way valve:
Controls refrigerant flow direction. Closed in cooling mode and open in heating mode. When closed, the air side heat
exchanger functions as a condenser and water side heat exchanger functions as an evaporator; when open, the air
side heat exchanger functions as an evaporator and water side heat exchanger function as a condenser.
7. High and low pressure switches:
Regulate refrigerant system pressure. When the refrigerant system pressure rises above the upper limit or falls below
the lower limit, the high or low pressure switches turn off, stopping the compressor.
8. Discharge temperature switch:
Protects the compressor from abnormally high temperatures and transient spikes in temperature.
9. Air purge valve:
Automatically removes air from the water circuit.
10. Safety valve:
Prevents excessive water pressure by opening at 43.5psi (3bar) and discharging water from the water circuit.
11. Water flow switch:
Detects water flow rate to protect the compressor and water pump in the event of insufficient water flow.
12. Water pump:
Circulates water in the water circuit.
13. Pressure sensor:
Measures refrigerant system pressure.
14. Crankcase heater:
Prevents refrigerant from mixing with compressor oil when the compressors are stopped.
15. Water side heat exchanger electric heater:
Protects the water side heat exchanger from ice formation.
16. Water flow switch electric heater:
Provides additional heating when heating capacity provided by the heat pump is insufficient due to low ambient
temperatures, it also protects external water pipes from freezing.
17. Solenoid valve SV4:
Returns oil to the compressor. It opens after 17 minutes of compressor operation, closes after 3 minutes, then opens
again for 3 minutes at 17 minute increments.
18. Plate heat exchanger:
In cooling mode, it can improve super-cooling degree and the super-cooled refrigerant can achieve better heat
exchange in indoor side. In heating mode, the refrigerant comes from the plate heat exchanger going to the
compressor can enhance the refrigerant enthalpy and improve the heating capacity in low ambient temperature.
Refrigerant volume in plate heat exchanger is controlled according to temperature different between plate heat
exchanger inlet and outlet.

19
Part 2 - Component Layout and Refrigerant Circuits
19. Pressure gauge joint (high and low pressure side):
Charges or discharges refrigerant.
20. Capillary:
Throttles and reduces pressure in the liquid injection cooling pipe.
21. Solenoid valve SV2:
Control the on-off of the liquid injection. It opens at the maximum discharge temperature reaching 105°C
while it closes at the maximum discharge temperature below 95°C or both the maximum discharge temperature
below 100°C and minimum discharge temperature below 90°C .