Mitsubishi Heavy Industries SRK100VNXWZRF Service Manual page 23

(c) Switching of defrost control with SW3-1
(i) If SW3-1 on the outdoor control PCB is turned to ON, it becomes easier to enter the defrost operation. Use this
when installing a unit at snowing regions.
(ii) Control contents
1) It allows entering the defrost operation under the defrost condition A when the cumulative heating operation time
becomes 30 minutes. It is 37 minutes at SW3-1 OFF (Factory default).
2) It allows entering the defrost operation under the defrost condition B when the cumulative heating operation time
becomes 25 minutes. It is 30 minutes at SW3-1 OFF (Factory default).
3) It allows the defrost operation with the outdoor heat exchanger temperature (Tho-R) and suction pressure
saturation temperature (SST) being higher than normal.
(6) Protective control/anomalous stop control by compressor's number of revolutions
(a) Compressor discharge pipe temperature protection
(i) Protective control
As the discharge pipe temperature (detected with Tho-D) exceeds the setting value, the compressor speed is
controlled to suppress the rise of discharge pipe temperature.
(ii) Anomalous stop control
1) If the discharge pipe temperature (detected with Tho-D) exceeds the setting value, the compressor stops.
2) When it is detected 2 times within 60 minutes or after continuous 30 minutes, including the stop of compressor,
E36 is displayed on the remote control and it enters the anomalous stop mode.
(iii) Reset of anomalous stop mode
As it drops to the reset value of 85°C or lower for 45 minutes continuously, it becomes possible to restart from the
remote control.
(b) Cooling high pressure protection
(i) Protective control
1) When the outdoor air temperature (Tho-A) is 40°C or higher and the outdoor heat exchanger temperature (Tho-R)
exceeds the setting value, the compressor speed is controlled to suppress the rise of high pressure.
2) Control value A is updated to an optimum value automatically according to the operating conditions.
(ii) Anomalous stop control
1) As the outdoor heat exchanger temperature (Tho-R) exceeds the setting value, the compressor stops.
2) If it is detected 5 times within 60 minutes or 63°C or higher continues for 30 minutes, including the stop of
compressor, E35 is displayed on the remote control and it enters the anomalous stop mode.
(iii) Reset of anomalous stop mode
As it reaches the reset value of 51°C or lower, it becomes possible to restart from the remote control.
Release
100
Discharge pipe temperature (°C)
Compressor operation
85
Discharge pipe temperature (°C)
Reduces compressor
speed at each minute.
Reset
A
Outdoor heat exchanger temperature (°C)
Compressor operation
51
Outdoor heat exchanger temperature (°C)
-
Reduces compressor
speed at each minute.
Retention
103
Compressor stop
115
Compressor stop
63
22
-
'22 • PAC-SM-422
Control value A
59-53°C