Outdoor Control Circuit; Outdoor Controls - Toshiba RAV-SP454ATP-E Service Manual

7-1. Outdoor Controls

1. PMV (Pulse Motor Valve) control
1) PMV is controlled between (SP40 to SP56: 20 to 500, SP80: 30 to 500) pulsed during operation.
2) In cooling operation, PMV is usually controlled with the temperature difference between TS sensor and
TC sensor aiming (SP40 to SP56: 2 to 5K, SP80: 1 to 4K) as the target value.
3) In heating operation, PMV is usually controlled with the temperature difference between TS sensor and
TE sensor aiming (SP40 to SP56: –2 to 4K, SP80: 2 to 4K) as the target value.
4) When the cycle excessively heated in both cooling and heating operation, PMV is controlled by TD sensor.
The target value is 101°C for both cooling and heating operations in SP40 to SP56, and 91°C for cooling
operation and 96°C for heating operation respectively in SP80.
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 or the
refrigerating cycle of each sensor after repair and then start the operation.
2. Discharge temperature release control
1) When the discharge temperature did not fall or the discharge temperature rapidly went up by PMV
control, this control lowers the operation frequency.
It subdivides the frequency control up to 0.6Hz to stabilize the cycle.
2) When the discharge temperature detected an abnormal stop zone, the compressor stops and then
restarts after 2 minutes 30 seconds.
The error counting is cleared when the operation continued for A minutes. If the error is detected by
B times without clearing, the error is determined and restarting is not performed.
∗ The cause is considered as excessively little amount of refrigerant, PMV error or clogging of the cycle.
3) For displayed contents of error, confirm on the check code list.
SP40 to SP56 in the
parentheses
SVM-12085_001-050.indd 38 SVM-12085_001-050.indd 38

7. OUTDOOR CONTROL CIRCUIT

TD [˚C]
(117) 111
Frequency normal down
(107) 109
Frequency slow down
(105) 106
(102) 103
Frequency slow up
(93) 96
Abnormal stop
Frequency hold
(Up to command)
As command is
– 38 –
FILE NO. SVM-12085
SP40 to SP80
SP56
A 6 10
B 8 4
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