Midea MV6-252WV2GN1 Service Manual page 42

Figure 3-5.3: Compressor priority and rotation – three outdoor units
① No. 1
② No. 3
③
No. 2
BP
No. 1 No. 2 No. 3
①
No. 4 No. 5 No. 1
②
③
No. 2 No. 3 No. 4
BP1 BP2 BP1
5.5 Electronic Expansion Valve Control
EXVA and EXVB control
The positions of electronic expansion valves EXVA and EXVB are controlled in steps from 0 (fully closed) to 480 (fully
open).
In cooling mode:
 When all outdoor units are in standby:
 All EXVAs and EXVBs are at position 352 (steps).
 When some outdoor units are running and some outdoor units are in standby:
 EXVAs and EXVBs on running outdoor units are controlled according to discharge temperature. EXVAs and EXVBs
of units in standby are fully closed.
 When all outdoor units are running:
 All EXVAs and EXVBs are controlled according to discharge temperature.
In heating mode:
 When all outdoor units are in standby:
 All EXVAs and EXVBs are at position 352 (steps).
 When some outdoor units are running and some outdoor units are in standby:
 EXVAs and EXVBs on running outdoor units are controlled according to discharge superheat. EXVAs and EXVBs of
units in standby are fully closed.
 When all outdoor units are running:
 All EXVAs and EXVBs are controlled according to discharge superheat.
EXVC control
The positions of electronic expansion valves EXVC are controlled in steps from 0 (fully closed) to 480 (fully open).
In cooling / heating mode:
 When all outdoor units are in standby:
No. 2 No. 3
No. 1 No. 2
No. 3 No. 1
BP BP
No. 4 No. 5
No. 2 No. 3
No. 5 No. 1
BP2 BP
No. 1 No. 2 No. 3
①
No. 3 No. 4 No. 1
②
No. 2 No. 3 No. 4
③
BP1 BP2 BP
No. 1 No. 2 No. 3
①
② No. 5 No. 6 No. 1
③
No. 3 No. 4 No. 5
BP1 BP2 BP1
V6 VRF 50/60Hz
No. 4
No. 2
No. 1
BP
No. 4 No. 5 No. 6
No. 2 No. 3 No. 4
No. 6 No. 1 No. 2
BP2 BP1 BP2
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