Freeze-Up Protection Control Or High Pressure Control - Daikin CTXS09GVJU Service Manual

SiUS12-814
5.4

Freeze-up Protection Control or High Pressure Control

A5
Remote
Controller
Display
Method of
Malfunction
Detection
Malfunction
Decision
Conditions
Supposed
Causes
Service Diagnosis
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.
High pressure control
During heating operations, the temperature detected by the indoor heat exchanger thermistor is
above 149°F
Freeze-up protection
When the indoor unit heat exchanger temperature is below 32°F during cooling operation.
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.
Troubleshooting
115