Mitsubishi Electric PQHY-P72ZLMU-A Service Handbook page 334

[ IX Troubleshooting ]
-4- LEV
LEV operation
The LEV on the indoor unit and LEV1, LEVINV, LEV6, and LEV7 on the heat source unit are driven by the pulse signal from
the circuit board on the indoor and heat-source units and are controlled by a stepping motor
(1) Indoor LEV and heat source LEV (LEV6,LEV7), and BC controller LEV (LEV1, LEV2, LEV3)
The valve opening changes according to the number of pulses.
1) Control boards (indoor unit and BC controller) and LEV (indoor unit LEV and BC controller LEV)
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 (indoor unit, Heat source unit, and BC controller) and LEV (indoor unit LEV, Heat source unit, and BC controller
LEV)
LEV
Blue
4
Red
6
M
Yellow
2
5
1
White Orange
HWE15150
Intermediate connector
Brown
2
Red
5
Blue
1
4
Orange
3
3
Yellow
2
4
6 White
1
Brown
ø4 Blue
ø3 Orange
ø2 Yellow
ø1
White
- 325 -
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
GB