Troubleshooting Lev Problems; General Overview On Lev Operation - Mitsubishi Electric PUHY-HP72 Service Handbook

[8-8 Troubleshooting LEV Problems ]

8-8

Troubleshooting LEV Problems

8-8-1

General Overview on LEV Operation

LEV (Indoor unit: Linear expansion valve) and LEV2 (Outdoor unit: Linear expansion valve) are stepping-motor-driven valves
that operate by receiving the pulse signals from the indoor and outdoor unit control boards.
(1) Indoor LEV and Outdoor LEV (LEV2)
The valve opening changes according to the number of pulses.
1) Indoor unit control board and the LEV (Indoor unit: Linear expansion valve)
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) Outdoor unit control board and the LEV (Outdoor unit: Linear expansion valve)
LEV
Blue
4
Red
6
M
Yellow
2
5
1
White
Orange
HWE18240_GB
Intermediate connector
Brown
2
Red
5
Blue
1
4
Orange
3
3
Yellow
2
4
6 White
1
Red
ø4 Blue
Orange
ø3
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
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