Sanyo 2-WAY ECO-i SPW-C0705DXHN8 Service Manual page 135

4. W-2WAY ECO-i Alarm Codes
P03, P17, P18 Alarm
Alarm code P03, P17, P18
Alarm meaning Compressor 1 discharge temperature trouble; Compressor 2 discharge temperature trouble;
Compressor 3 discharge temperature trouble
Alarm conditions Temperature is 106°C or higher and pre-trip stop has occurred.
The alarm occurs when pre-trip stop occurs more than once. However the pre-trip counter is
cleared if the compressor operates continuously for a specifi ed length of time.
Probable cause (1) Clogging of liquid valve capillaries
(2) Insuffi cient amount of refrigerant (including trouble resulting from an insuffi cient initial charge
and from gas leakage)
(3) Blocking of low-pressure parts caused by intrusion of foreign objects (moisture, scale, etc.)
(4) Crossing (tubing or PCB connectors) with the other compressor thermistor
(5) Expansion valve operation failure
(6) Accumulation of refrigerant at stopped outdoor units
(7) Compressor discharge sensor failure
(8) PCB failure (A/D conversion failure)
(9) Electrical noise
Check (1) Clogging of capillaries
Trouble: Compressor discharge temperature does not decrease even when the liquid valve
Check:
(2) Insuffi cient refrigerant
Trouble: Liquid effectiveness is poor.
Check:
(3) Foreign object intrusion
Trouble: Liquid valve effectiveness is poor.
Check:
(4) Crossed thermistor
Trouble: The discharge temperature of the other compressor is high although only this
(5) Accumulation of refrigerant in stopped outdoor units
Trouble: • System is OK when all outdoor units are operating, however symptoms of
Check: • Representative parts include the liquid capillaries (secondary side of capillaries will
(6) Sensor failure
Check: • This alarm is likely to occur when wiring is partially cut. (It is diffi cult to identify, even
(7) If the cause is still unknown after checking the above, then it is possible that electrical noise
is the cause of the trouble.
Correction (1) Replace the sensor.
(2) Replace the outdoor unit PCB.
(3) Correct the problem locations.
Example All of the probable causes
Notes Operates continuously for a set length of time.
Indicates 2.5 minutes or longer for an inverter unit and 30 seconds or longer for a constant-
speed compressor.
is ON.
When the liquid valve is operating and the liquid valve is ON, check that the
secondary side of the liquid capillaries is cold.
Check whether or not the superheating temperature is declining if the evaporator
mechanical valve is opened to 300 pulses or more (after checking for foreign object
intrusion).
Check that there is no difference in the condensation or frost conditions between
the strainer primary-side and secondary-side tubing.
compressor is operating.
When the liquid valve turns ON, the discharge temperature of the other compressor
decreases.
insuffi cient gas occur when a certain outdoor unit is stopped.
• Condensation or frost is visible up to the top of the accumulator of the stopped
outdoor unit.
• After an outdoor unit stops, there is the sound of refrigerant fl owing into an outdoor
unit that was stopped for a long time.
• When an outdoor unit starts after being stopped for a long time, the start is
accompanied by much vibration.
be cool during cooling operation), mechanical valve, mechanical valve bypass check
valve (sound of refrigerant fl ow can be heard, and stops when the liquid valve is
closed), hot gas defrost valve (if valve secondary side remains hot even after much
time has passed, be careful not to mistake transmitted heat for a valve failure).
• Ice is growing on the lower parts of some outdoor unit heat exchangers but not on
others.
Because this trouble may occur even in outdoor units with a high operating rate
under conditions of insuffi cient gas, caution is needed.
when continuity is checked.) The detected discharge temperature is high.
• Although such conditions rarely occur, a P02 alarm is likely if the detected discharge
temperature is low.
• Replace the sensor with another discharge sensor and compare the temperature
conditions.
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W-2WAY ECO-i SYSTEM
Trouble Diagnosis
5