Freeze-Up Protection Control Or High Pressure Control - Daikin FTXS09HVJU Service Manual

SiUS04-904
4.3

Freeze-up Protection Control or High Pressure Control

A5
Remote
Controller
Display
 High pressure control
Method of
Malfunction
Detection
 Freeze-up protection control (operation halt) is activated during cooling operation according to
 High pressure control
Malfunction
Decision
Conditions
 Freeze-up protection
 Operation halt due to clogged air filter of the indoor unit.
Supposed
 Operation halt due to dust accumulation on the indoor unit heat exchanger.
Causes
 Operation halt due to short-circuit.
 Detection error due to faulty indoor unit heat exchanger thermistor.
 Detection error due to faulty indoor unit PCB.
100
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 temperature detected by the indoor unit heat exchanger thermistor.
During heating operations, the temperature detected by the indoor heat exchanger thermistor is
above 149°F
(65°C)
When the indoor unit heat exchanger temperature is below 32°F
Troubleshooting
(0°C) during cooling operation.
Service Diagnosis