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Troubleshooting
Si12-308
174
Service Diagnosis
5.4
Freeze-up Protection Control or High Pressure Control
Remote
Controller
Display
A5
Method of
Malfunction
Detection
High pressure control (heat pump model only)
During heating operations, the temperature detected by the indoor heat exchanger
thermistor is used for the high pressure control (stop, outdoor fan stop, etc.)
The freeze-up protection control (operation halt) is activated during cooling operation
according to the temperature detected by the indoor unit heat exchanger thermistor.
Malfunction
Decision
Conditions
High pressure control
During heating operations, the temperature detected by the indoor heat exchanger
thermistor is above 65°C
Freeze-up protection
When the indoor unit heat exchanger temperature is below 0°C during cooling operation.
Supposed
Causes
Operation halt due to clogged air filter of the indoor unit.
Operation halt due to dust accumulation on the indoor unit heat exchanger.
Operation halt due to short-circuit.
Detection error due to faulty indoor unit heat exchanger thermistor.
Detection error due to faulty indoor unit PCB.
Summary of Contents for Super Multi NX B series
Page 7: ...Si12 308 vi Table of Contents ...
Page 29: ...List of Functions Si12 308 18 List of Functions ...
Page 71: ...Specifications Si12 308 60 Specifications ...
Page 175: ...Instruction Si12 308 164 System Configuration ...
Page 227: ...Check Si12 308 216 Service Diagnosis ...
Page 288: ...Si12 308 Wiring Diagrams Appendix 277 FTXD50BVMC FTXD60 71BVMC ...
Page 299: ...Si12 308 iv Index ...