Toshiba MM-A0160HX, Service Manual

Page: 34 / 135

35
11
Outline of Control
Outdoor Unit
Item Operation explanation and applied data, etc. Remarks
4. Oil level valve
detection
control
1) The volume of oil in the oil tank is judged by the
detection temperature of TK1 and TK2 sensors.
2) The present temperature detected by TK1,TK2 and
TK3 sensors are stored in memory as the initial
value, and then the solenoid valve SV3C is
activated. Sampling of TK1,TK2 and TK3 sensor
temperature occurs and the temperature change
between TK1 and TK2 is judged. If the judgement is
such that a reduction in oil is present the oil
equalizing control function starts.
3. Capacity
calculation
By the capacity request command from the indoor
controller, the inverter operation command of the
master outdoor unit, ON/OFF control of the fixed-
speed compressor and the slave outdoor unit are
determined. The master outdoor unit sets up activation
priority order of the slave outdoor units connected to
the system, and starts the operation.
<Example of 30HP system>
(HP)
30
25
20
15
10
5
1
R
equested HP
5 10 15 20 25 30 (HP)
Operation capacity
2b. Outdoor fan
control
(1) Heating fan control
1) The number of waves is controlled according to
the TE sensor temperature.
2) If TE >20°C is constantly detected for 5 minutes,
the operation will automatically shut down. This
is the same condition as when the thermostat
automatically becomes switched off, thus the
operation will automatically start again.
3) When the above condition (2) persists and the
high pressure SW operates, check the suction
area of the indoor unit for blockages. Ensure that
the filter is clean and start the operation.
4) After the fan is switched on, this control does
not operate during defrost mode.
TE temperature
(°C) A zone: minimum, compulsory stop timer count
20
B zone: 2/20 seconds (down to the minimum)
6
C zone: 1/20 seconds (down to the minimum)
4
D zone: hold (maintain the current rate)
2
E zone: +1/20 seconds (up to the maximum)
1
F zone: Maximum revolutions number (16)
Fixed speed/slave units not operating will maintain
the ODU fan at 1 wave to prevent refrigerant from
remaining in the ODU Heat Exchanger.
11
Inverter
Fixed