Mitsubishi Electronics MUY-ANA Heat Pump User Manual


 
23
The table below shows the role of Exclusive LEV and Receiver LEV in each operation mode.
wIn COOL mode, the two indoor coil thermistor (one main and one sub) sense temperature ununiformity (super heat) at the
heat exchanger, and when temperature difference have developed, the indoor coil thermistors adjust LEV opening to dimin-
ish the super heat.This action is called Evaporation Temperature Protection.
Circulation
Amount
Control
High
Pressure
Protection
wEvaporation
Temperature
Protection
Discharge
Temperature
Protection
Capacity
Distribution
COOL
Exclusive LEV
Receiver LEV
Exclusive LEV
Receiver LEV
HEAT
Indoor heat
exchanger
(MXZ-3A)
Outdoor
heat
exchanger
Exclusive
LEV
Receiver
LEV
Receiver
The opening pulse of the Receiver LEV is fixed to the standard No.3 in cooling operation, and so is that of each Exclusive
LEV in heating operation.
However the opening pulse will be changed to the standard No.4 or No.5 when the discharge temperature protection or high-
pressure protection is working.
In addition to that, it will also be changed to standard No.2 or No.1 when the opening pulse of the each Exclusive LEV
becomes 100 pulse or less in cooling operation or so does that of Receiver LEV in heating operation.
1
2
3
4
5
200
300
400
450
500
Standard No.
Number of
operating
indoor units
<MXZ-2A>
1 unit
150
320
360
410
500
2 units
120
140
160
220
280
1 unit
120
140
160
220
280
2 units
COOL
LEV opening (pulse)
HEAT
1
2
3
4
5
150
250
350
400
450
Standard No.
Number of
operating
indoor units
<MXZ-3A>
1 unit
250
320
360
410
460
2 units
250
320
370
420
470
3 units
250
300
450
460
470
1 unit
250
300
380
400
450
2 units
250
300
380
390
440
3 units
COOL
LEV opening (pulse)
HEAT
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