Mitsubishi Electric R410A Service Handbook page 268

[8-8 Troubleshooting LEV Problems ]
3) Pulse signal output and valve operation
Output
(phase)
number
1
1 ON
2 ON
3 OFF
4 OFF
4) LEV closing and opening operation
Valve closed
A
E
B
80 - 100 pulses
HWE14080
Output state
2 3 4
OFF OFF ON
ON OFF OFF
ON ON OFF
OFF ON ON
D
C
Valve open
Fully open
. 1400 pulses (indoor unit LEV) *1
. 2100 pulses (outdoor unit LEV) *1
Pulses
Output pulses change in the following orders when the
Valve is closed; 1
Valve is open; 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.
*Upon power on, the indoor unit circuit board sends a 2200 pulse
signal to the indoor unit LEV and a 3200 pulse signal to the outdoor
unit LEV to determine the valve position and always brings the valve to
the position as indicated by " A " in the diagram.
When the valve operates smoothly, no sound from LEV or no vibration
occurs, however, when the pulses change from E to A in the chart or
the valve is locked, a big sound occurs.
*Whether a sound is generated or not can be determined by
holding a screwdriver against it, then placing your ear against the handle.
*1 The LEV opening may become greater depending on the operation status.
- 259 -
2 3 4 1
3 2 1 4
GB