Daikin FTKS20CVMB, Service Manual

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Troubleshooting SiENBE04-401A
122 Service Diagnosis
4.12 Discharge Pipe Temperature Control
Remote control
Display
F3
Method of
Malfunction
Detection
The discharge pipe temperature control (stop, frequency drooping, etc.) is checked with the
temperature being detected by the discharge pipe thermistor.
Malfunction
Decision
Conditions
„
If a stop takes place 4 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 °C, the
compressor will stop. (The error is cleared when the temperature has dropped below
°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).
Supposed
Causes
„ Refrigerant shortage
„ Four way valve malfunctioning
„ Discharge pipe thermistor defective
(heat exchanger or outdoor air temperature thermistor defective)
„
Outdoor unit PCB defective
„ Water mixed in the local piping
„ Electronic expansion valve defective
„ Stop valve defective
Troubleshooting
Check No.4
Refer to P.138
Check No.6
Refer to P.140
Check No.11
Refer to P.143
Stop temperatures
(A)RK(X)S (A)RK(X)H, R(Y)N
(1) above 45Hz (rising), above 40Hz (dropping) 110 97 85
(2) 30~45Hz (rising), 25~40Hz (dropping) 105 92 80
(3) below 30Hz (rising), below 25Hz (dropping) 99 86 74
Replace a defective
thermistor.
Replace the valve itself or
the coil.
Refer to the refrigerant line
check procedure.
Replace the outdoor unit
PCB.
(R2846)
Caution
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.
Check No. 6
Check the thermistors.
Malfunctioning
z
Discharge pipe thermistor
z
Outdoor unit heat exchanger thermistor
z
Outdoor temperature thermistor
z
Refrigerant shortage
z
Four way valve malfunctioning
z
Water mixed
z
Stop valve defective
Malfunctioning
Functioning
Functioning
Functioning
Check No. 11
Check the refrigerant line.
Malfunctioning
Check No. 4
Check the electronic expansion
valve.