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Troubleshooting
SiUS12-928_A
143
Service Diagnosis
5.25 Refrigerant Shortage
Remote
Controller
Display
U0
Outdoor Unit LED
Display
A
1
2
3
4
Method of
Malfunction
Detection
Refrigerant shortage detection I :
Refrigerant shortage is detected by checking the input current value and the compressor output
frequency. If the refrigerant is short, the input current is smaller than the normal value.
Refrigerant shortage detection II :
Refrigerant shortage is detected by checking the discharge pipe temperature and the opening of
the electronic expansion valve. If the refrigerant is short, the discharge pipe temperature tends to
rise.
Malfunction
Decision
Conditions
Refrigerant shortage detection I :
The following conditions continue for 7 minutes.
<18 class>
DC current x DC voltage
≤
x Compressor output fre
Output frequency >
<24/32 class>
DC current
≤
x Compressor output fre
Output frequency >
Refrigerant shortage detection II :
The following conditions continue for 80 seconds.
Opening of the electronic expansion valve
≥
Discharge pipe temperature (°C) >
x target discharge pipe temperature (°C) +
(°C)
(Discharge pipe temperature (°F) >
x target discharge pipe temperature (°F) +
(°F))
If the error repeats 4 times, the system is shut down.
Reset condition: Continuous run for about 60 minutes without any other error
Supposed
Causes
Refrigerant shortage (refrigerant leakage)
Poor compression performance of compressor
Disconnection of the discharge pipe thermistor, indoor or outdoor heat exchanger thermistor,
room or outdoor temperature thermistor
Closed stop valve
Defective electronic expansion valve
(–)
(W)
(Hz)
1756/256
50
55
(–)
(A)
(Hz)
27/1000
2
40
(pulse)
(–)
(°C)
(°F)
Cooling
450
255/256
20
36.1
Heating
255/256
40
72.1
Summary of Contents for SUPER MULTI NX G Series
Page 1: ...SiUS12 928_A Applied Models Inverter Multi Heat Pump G Series J Series...
Page 7: ...SiUS12 928_A Table of Contents vi...
Page 10: ...SiUS12 928_A 1 List of Functions Part 1 List of Functions 1 Functions 3...
Page 11: ...SiUS12 928_A List of Functions 2...
Page 17: ...SiUS12 928_A Specifications 8...
Page 23: ...SiUS12 928_A Specifications Specifications 14...
Page 25: ...SiUS12 928_A Printed Circuit Board Connector Wiring Diagram 16...
Page 37: ...SiUS12 928_A Function and Control 28...
Page 69: ...SiUS12 928_A Control Specification Function and Control 60...
Page 71: ...SiUS12 928_A Operation Manual 62...
Page 73: ...SiUS12 928_A Duct Free System Operation Manual 64 2 Duct Free System 2 1 Remote Controller...
Page 84: ...Duct Free System SiUS12 928_A 75 Operation Manual...
Page 85: ...SiUS12 928_A Duct Free System Operation Manual 76 2 8 TIMER Operation...
Page 86: ...Duct Free System SiUS12 928_A 77 Operation Manual...
Page 87: ...SiUS12 928_A Duct Free System Operation Manual 78 2 9 Note for Multi System...
Page 88: ...Duct Free System SiUS12 928_A 79 Operation Manual...
Page 97: ...SiUS12 928_A Slim Duct Built In System Operation Manual 88...
Page 99: ...SiUS12 928_A Service Diagnosis 90...
Page 169: ...SiUS12 928_A Removal Procedure 160...
Page 225: ...SiUS12 928_A Trial Operation and Field Settings 216...
Page 235: ...SiUS12 928_A Appendix 226...