Mitsubishi Electric MUFZ-KW25VG-E1 Service Manual page 45

K Check of LEV (Expansion valve)
Turn ON the power supply.
<Preparation of the remote controller>
While pressing both Operation select button and
TEMP button on the remote controller at the same
time, press RESET button.
First, release RESET button.
Hold down the other 2 buttons for another 3 seconds.
Make sure that the indicators on the LCD screen
shown in the right figure are all displayed. Then re-
lease the buttons.
Press OFF/ON (stop/operate) button of the remote con-
troller (the set temperature is displayed) with the remote
controller headed towards the indoor unit. *1
Expansion valve operates in full-opening direction.
Do you hear the expansion valve "click,
click·······"?
Do you feel the expansion valve vibrate
when touching it ?
No
Is LEV coil properly fixed to
the expansion valve?
Yes
Does the resistance of LEV
coil have the characteristics?
(Refer to 12-4.)
No
Replace the LEV coil.
NOTE: After check of LEV, take the following steps.
1. Turn OFF the power supply and turn it ON again.
2. Press RESET button on the remote controller.
OBH895
OK
Yes
Properly fix the LEV coil to the expansion valve.
No
Measure each voltage between connector
pins of CN724 on the inverter P.C. board.
1. Pin (-) — Pin (+)
2. Pin (-) — Pin (+)
3. Pin (-) — Pin (+)
Yes
4. Pin (-) — Pin (+)
Is there about 3 - 5 V AC between each?
NOTE: Measure the voltage by an analog
tester.
Replace the expansion valve.
*1. Regardless of normal or abnormal condition, a short beep is
emitted once the signal is received.
Yes
45
AM PM AM PM
Replace the inverter P.C.
No board.