Freeze-Up Protection Control Or High Pressure Control - Daikin B-Series Service Manual

Si06-313
4.3

Freeze-up Protection Control or High Pressure Control

A5
Remote
Controller
Display
Method of
Malfunction
Detection
Malfunction
Decision
Conditions
When the indoor unit heat exchanger temperature is below 0°C during cooling operation.
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 65°C
Freeze-up protection
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
73