Troubleshooting Lev Problems; General Overview On Lev Operation - Mitsubishi Electric HP120TNU-A Service Handbook

[8-8 Troubleshooting LEV Problems ]

8-8

Troubleshooting LEV Problems

8-8-1

General Overview on LEV Operation

LEV operation
LEV are stepping-motor-driven valves that operate by receiving the pulse signals from the indoor and outdoor unit control
boards.
(1) Outdoor LEV (LEV2a, 2b, and 2d), Indoor LEV and BC controller LEV
The valve opening changes according to the number of pulses.
1) Control boards (indoor unit) and LEV (indoor unit LEV and BC controller LEV 3 (KB type))
LEV
Blue
4
Brown
6
M
Yellow
2
5
1
White Red Orange
Note. The connector numbers on the intermediate connector and the connector on the control board differ. Check the color of the lead wire
to judge the number.
2) Control boards (outdoor unit and BC controller), LEV (BC controller LEV1, LEV3 (J, JA, KA types), LEV4) and the outdoor unit
LEV (LEV2a, 2b, and 2d)
LEV
Blue
4
Red
6
M
Yellow
2
5
1
Orange
White
24
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Intermediate connector
Brown
2
Red
5
Blue
1
4
Orange
3
3
Yellow
2
4
6 White
1
Red
ø4 Blue
ø3 Orange
ø2 Yellow
ø1
White
Control board
DC12V
6
5
Drive circuit
4
4
3
3
2
2
1
1
Control board
DC12V
6
5
Drive circuit
ø4
4
ø3
3
ø2
2
ø1
1
HWE18220_GB