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14. Protection Control
14.1 Restart Control (Time Delay Safety Control)
The compressor will not turn on within 3 minutes from the moment operation stops, although the unit is turned on
again by pressing OFF/ON button at remote control within this period.
This control is not applicable if the power supply is cut off and on again.
This phenomenon is to balance the pressure inside the refrigerant cycle.
14.2 30 Seconds Forced Operation
Once the air conditioner is turned on, the compressor will not stop within 30 seconds in a normal operation
although the intake air temperature has reached the thermo-off temperature. However, force stop by pressing the
OFF/ON button at the remote control is permitted or the Auto OFF/ON button at indoor unit.
The reason for the compressor to force operation for minimum 30 seconds is to allow the refrigerant oil run in a
full cycle and return back to the outdoor unit.
14.3 Total Running Current Control
When the outdoor unit total running current (AC) exceeds X value, the frequency instructed for compressor
operation will be decreased.
If the running current does not exceed X value for 10 seconds, the frequency instructed will be increased.
However, if total outdoor unit running current exceeds Y value, compressor will be stopped immediately for
3 minutes.
Model
VU9***
VU12***
VU18***
Operation Mode
X (A)
Y (A)
X (A)
Y (A)
X (A)
Y (A)
Cooling / Soft Dry (A)
7.0
15.0
7.0
15.0
9.6
15.0
Cooling / Soft Dry (B)
6.4
15.0
6.4
15.0
9.3
15.0
The first 30 minutes of cooling operation, (A) will be applied.
14.4 IPM (Power Transistor) Prevention Control
DC Peak Current Control
o
When electric current to IPM exceeds set value of 13.2 A (VU9SK), 13.1 A (VU12SK), 17.1 A (VU18SK)
within 30 seconds, the compressor will stop operation. Then, operation will restart after 1 minute.
o
For second occurrence onwards, if the set value exceeds again within 30 seconds, the compressor will stop
operation. Then, operation will restart after 3 minutes.
o
If this condition repeats continuously for 7 times, all indoor and outdoor relays will be cut off, timer LED will
be blinking (“F99” is indicated).
Overheating prevention
o
When the IPM temperature rises to 120°C the compressor will stop immediately.
o
Compressor operation restarts after 3 minutes the temperature decreases to 110°C.
o
If this condition repeats continuously 4 times within 20 minutes, timer LED will be blinking (“F96” is indicated).
(B)
(A)
Outdoor air temperature
39°C
38°C
