Service Manual

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2. Discharge temperature release control
1) This function controls the operation
frequency, that is, lowers the operation
frequency when the discharge temperature
has not lower or the discharge temperature
has rapidly risen during PMV control.
It subdivides the frequency control up to a
unit of 0.6 Hz to stabilize the cycle.
2) When the discharge temperature is detected
in an abnormal stop zone, the unit stops the
compressor and restarts after 2 minutes
30 seconds.
The error counter is cleared when it has
continued the operation for 6 minutes.
If the abnormal stop zone has been detected
by 8 times without clearing of counter, an
error “P03” is displayed.
∗ The cause is considered as excessively
little amount of refrigerant, defective PMV,
or clogging of cycle.
3. Current release control
The output frequency and the output voltage are
controlled by AC current value detected by T02
on the outdoor P.C. board so that input current of
the inverter does not exceed the specified value.
Objective model
I1 value [A]
SP40, SP45
COOL HEAT
10.13 10.50
I1
I1–0.5
Current [A]
117
107
103
100
93
TD [˚C]
Frequency down
Normal operation
Hold
Hold
Error stop
(“P03” display with 8 times error count)
Frequency down
Frequency slow-down
Frequency holding
Frequency slow-up
(Up to command)
As command is
<In case of RAV-SP40 and SP45 models>
1. Pulse Motor Valve (PMV) control
1) For PMV with 50 to 500 pulses during operation, respectively.
2) In cooling operation, PMV is controlled with the temperature difference between TS sensor and TC sensor.
3) In heating operation, PMV is controlled with the temperature difference between TS sensor and TE sensor.
4) For the temperature difference in items 2) and 3), 1 to 5K is aimed as the target in both cooling and
heating operations.
5) When the cycle excessively rose in both cooling and heating operations, PMV is controlled by TD sensor.
The aimed value is usually 106°C in both cooling and heating operations.
REQUIREMENT
A sensor trouble may cause a liquid back-flow or abnormal overheat resulting in excessive shortening of the
compressor life. In a case of trouble on the compressor, be sure to check there is no error in the resistance
value an the refrigerating cycle of each sensor after repair and then start the operation.