Mitsubishi P120 Air Conditioner User Manual


 
[ IX Troubleshooting ]
- 245 -
HWE09120 GB
-5- LEV
LEV operation
LEV (Indoor unit: Linear expansion valve), 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 (LEV2a, LEV2b)
The valve opening changes according to the number of pulses.
1) Indoor unit control board and the LEV (Indoor unit: Linear expansion valve)
2) Outdoor unit control board and the LEV (Outdoor unit: Linear expansion valve)
3) Pulse signal output and valve operation
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.
Control board
Drive circuit
LEV
M
5
5
2
2
1
1
3
3
4
4
6
6
DC12V
Red
Intermediate connector
Brown
Blue
Orange
Yellow
White
Red Orange White
Brown
Blue
Yellow
6
5
4
4
3
2
1
3
2
1
4
3
2
1
ø4
ø3
ø2
ø1
ø4
ø3
ø2
ø1
Control board
Drive circuit
LEV
M
5
2
1
3
4
6
DC12V
Brown
Blue
Orange
Yellow
White
Orange
White
Blue
Yellow
Red
6
5
4
3
2
1
Output state
Output
(phase)
number
1234
1 ON OFF OFF ON
2 ON ON OFF OFF
3 OFF ON ON OFF
4 OFF OFF ON ON
Output pulses change in the following orders when the
V
alve is closed; 1 2 3 4 1
Valve is open;
4 3 2 1 4
*1. When the LEV opening angle does not change,
all the output phases will be off.
*2. When the output is open phase or remains ON,
the motor cannot run smoothly, and rattles and vibrates.