SiUS04-904 Troubleshooting
120 Service Diagnosis
4.12.2 15/18/24 Class
Remote
Controller
Display
F3
Method of
Malfunction
Detection
The discharge pipe temperature control (stop, frequency dropping, etc.) is checked with the
temperature being detected by the discharge pipe thermistor.
Malfunction
Decision
Conditions
If a stop takes place 6 times successively due to abnormal discharge pipe temperature, the
system is shut down.
If the temperature being detected by the discharge pipe thermistor rises above 248°F (120°C),
the compressor stops. (The error is cleared when the temperature has dropped below
225°F(107°C).
Stop temperatures (variable by models)
(1) 230°F (110°C): above 45Hz (rising), above 40Hz (dropping)
(2) 216°F (102°C): 30~45Hz (rising), 25~40Hz (dropping)
(3) 208°F (97.8°C) : below 30Hz (rising), below 25Hz (dropping)
The error counter is reset 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 temperature thermistor defective)
Outdoor unit PCB defective
Water mixed in the local piping
Electronic expansion valve defective
Stop valve defective
Troubleshooting
Check No.04
Refer to P.144
Check No.06
Refer to P.146
Check No.11
Refer to P.156
(R7141)
Caution
Be sure to turn off the power switch before connecting or disconnecting
the connector, or parts damage may occur.
Malfunctioning
Discharge pipe thermistor
Outdoor unit heat exchanger thermistor
Outdoor temperature thermistor
Refrigerant shortage
Four-way valve malfunctioning
Water mixed
Stop valve defective
Functioning
Functioning
Functioning
Malfunctioning
Malfunctioning
Check No. 06
Check the thermistors.
Check No. 11
Check the refrigerant line.
Check No. 04
Check the electronic
expansion valve.
Replace the defective
thermistor.
Replace the valve itself or
the coil.
Refer to the refrigerant line
check procedure.
Replace the outdoor unit
PCB.