Discharge Pipe Temperature Control - Daikin B-Series Service Manual

Si04-306E

4.12 Discharge Pipe Temperature Control

F3
Remote
Controller
Display
Method of The discharge pipe temperature control (stop, frequency drooping, etc.) is checked with the
Malfunction temperature being detected by the discharge pipe thermistor.
Detection
Malfunction
Decision
Conditions
Stop temperatures (in case of 5.0kW class)
(1) 110°C : above 45Hz (rising), above 40Hz (dropping)
(2) 102°C : 30~45Hz (rising), 25~40Hz (dropping)
(3) 98°C : below 30Hz (rising), below 25Hz (dropping)
Supposed
Causes
Troubleshooting
Check No.04
Refer to P.142
Check No.06
Refer to P.144
Check No.11
Refer to P.147
Service Diagnosis
If a stop takes place 6 times successively due to abnormal discharge pipe temperature, the
system will be shut down.
If the temperature being detected by the discharge pipe thermistor rises above 120°C, the
compressor will stop. (The error is cleared when the temperature has dropped below
107°C.)
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).
Refrigerant shortage
Four way valve malfunctioning
Discharge pipe thermistor defective
(heat exchanger or outdoor temperature thermistor defective)
Outdoor unit PCB defective
Water mixed in the local piping
Electronic expansion valve defective
Stop valve defective
Be sure to turn off power switch before connect or disconnect connector,
Caution
or parts damage may be occurred.
Check No. 06
Check the thermistors.
Functioning
Check No. 04
Check the electronic
expansion valve.
Functioning
Check No. 11
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.
(R7141)
125