Mitsubishi Heavy Industries FDTC50ZHXV Technical Manual page 181

2) Defrosting end conditions
When any of the following conditions is satisfied, the defrosting end operation starts.
a) When it has elapsed 8 minutes and 20 seconds after the start of defrosting. (After 10 minutes and 20 seconds for model 71, 200 and 280)
b) When the outdoor unit heat exchanger temperatures (Tho-R1, R2), whichever the lower, becomes 12°C or higher
for 10 seconds continuously.
3) Switching of defrosting control with SW3-1
a) If SW3-1 on the outdoor unit control PCB is turned to ON, it becomes easier to enter the defrosting operation. Use
this when installing a unit at snowing regions.
b) Control contents
i) It allows entering the defrosting operation under the defrosting condition A when the cumulative heating
operation time becomes 30 minutes. It is 37 [45] minutes at SW3-1 OFF (Factory default).
ii) It allows entering the defrosting operation under the defrosting condition B when the cumulative heating
operation time becomes 25 minutes. It is 30 minutes at SW3-1 OFF (Factory default).
iii) It allows the defrosting operation with the outdoor unit heat exchanger temperature (Tho-R) and suction
pressure saturation temperature (SST) being higher than normal.
Note (1) Figures in [ ] are for model 71.
(f) Protective control/anomalous stop control by compressor's number of revolutions
1) Compressor discharge pipe temperature protection
a) Protective control
As the discharge pipe temperature (detected with Tho-D) exceeds the setting value, the compressor speed (frequency)
is controlled to suppress the rise of discharge pipe temperature.
Release
b) Anomalous stop control
i) If the discharge pipe temperature (detected with Tho-D) exceeds the setting value, the compressor stops.
ii) When it is detected 2 times within 60 minutes or after continuous 60 minutes, including the stop of compressor,
E36 is displayed on the remote controller and it enters the anomalous stop mode.
Compressor operation
c) Reset of anomalous stop mode
As it drops to the reset value of 85°C (90°C) or lower for 45 minutes continuously, it becomes possible to restart
from the remote controller.
Note (1) Figures in ( ) are for model 200, 250.
2) Cooling high pressure protection
a) Protective control
i) When the outdoor air temperature (Tho-A) is 40°C or higher and the outdoor unit heat exchanger temperature (Tho-R)
exceeds the setting value, the compressor speed (frequency) is controlled to suppress the rise of high pressure.
ii) Control value A is updated to an optimum value automatically according to the operating conditions.
Outdoor unit heat exchanger temp. (°C)
b) Anomalous stop control
i) As the outdoor unit heat exchanger temperature (Tho-R) exceeds the setting value, the compressor stops.
ii) If it is detected 5 times within 60 minutes or 65°C or higher continues for 60 minutes, including the stop of
compressor, E35 is displayed on the remote controller and it enters the anomalous stop mode.
Compressor operation
c) Reset of anomalous stop mode
As it reaches the reset value of 51°C or lower, it becomes possible to restart from the remote controller.
Reduces compressor
speed at each minute.
Retention
100 （ 105） 105 （ 110）
Discharge pipe temperature (°C)
85 （ 90） 115 （ 135）
Discharge pipe temperature (°C)
Reduces compressor
speed at each minute.
Reset
A
51 65
Outdoor unit heat exchanger temp. (°C)
Note (1) Figures in ( ) are for model 200, 250.
Compressor stop
Note (1) Figures in ( ) are for model 200, 250.
Compressor stop
173
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Model Control value A
71
100~140 54~60°C
200, 250