Discharge Pipe Temperature Control - Daikin CTXU25G2V1B Service Manual

SiBE12-908
2.21

Discharge Pipe Temperature Control

F3
Remote
Controller Display
Outdoor Unit LED A5
Display
Method of Discharge pipe temperature control (stop, frequency attenuation, etc.) is executed based on the
temperature detected by the discharge pipe thermistor.
Malfunction
Detection
Malfunction If the temperature being detected by the discharge pipe thermistor rises, the compressor will
stop. The temperature at which the compressor halts varies according to the frequency.
Decision
(1) 110°C when the frequency is above 30Hz on ascending or above 25Hz on descending.
Conditions
(2) 108°C when the frequency is below 30Hz on ascending or below 25Hz on descending.
Supposed
Causes
Troubleshooting
Check No.02
Refer to P.162
Check No.12
Refer to P.165
Check No.17
Refer to P.169
Service Diagnosis
55 ( - )
The error is cleared when the temperature has dropped below 95°C.
If the compressor stops 6 times successively due to abnormal discharge pipe temperature,
the system will be shut down.
The error counter will reset itself if this or any other error does not occur during the following
60-minute compressor running time (total time).
Insufficient gas
Faulty operation of four way valve
Defective discharge pipe thermistor
(Defective heat exchanger thermistor or outdoor air thermistor)
Defective outdoor unit PCB
Water mixed in the field piping
Defective electronic expansion valve
Defective stop valve
Be sure to turn off power switch before connect or disconnect connector,
Caution or parts damage may be occurred.
Check No. 02
Check the
thermistors.
Functioning
Check No. 17
Check the electronic
expansion valve.
Functioning
Check No. 12
Check the
refrigerant line.
Functioning
Malfunctioning
Discharge pipe thermistor
Outdoor unit heat exchanger thermistor
Outdoor temperature thermistor
Malfunctioning
Malfunctioning
Refrigerant shortage
Four way valve malfunctioning
Water mixed
Stop valve defective
Troubleshooting
Replace the defective
thermistor.
Replace the valve itself or
the coil.
Refer to the refrigerant line
check procedure.
Replace the outdoor unit
PCB.
(R9442)
131