Mitsubishi Electric Mr.Slim MUZ-GC25NA - C1, Service Manual

Page: 43 / 64

43
K Check of LEV (Expansion valve)
MUZ-GC50NA-
C1
MUZ-GC60/71NA
Turn ON power supply to the outdoor unit after checking
LEV coil is mounted to the LEV body securely.
Is "click - click" sound heard?
Or, do you feel vibration of the LEV coil with a hand?
Disconnect the connector CN795.
Is there normal resistance to LEV coil?
Normal
Replace the outdoor electronic control P.C. board.
Replace the LEV coil.
Yes
No
No
Yes
Replace the inverter P.C.
board. No
Press OPERATE/STOP (ON/OFF) button of the remote
controller (the set temperature is displayed) with the
remote controller headed towards the indoor unit. 1
Expansion valve operates in full-opening direction.
OK
NOTE : After check of LEV, do the undermentioned operations.
1. Turn OFF the power supply and turn ON it again.
2. Press RESET button on the remote controller.
1. Regardless of normal or abnormal condition, a short beep
is emitted once the signal is received.
Measure each voltage between connector
pins of CN724 on the inverter P.C. board.
1. Pin (-) — Pin (+)
2. Pin (-) — Pin (+)
3. Pin (-) — Pin (+)
4. Pin (-) — Pin (+)
Is there about 3 ~ 5 VAC between each?
NOTE : Measure the voltage by an analog
tester.
Properly fi x the LEV coil to the expansion valve.
Replace the LEV coil.
Replace the expansion valve.
Is LEV coil properly fi xed to
the expansion valve?
Does the resistance of LEV
coil have the characteristics?
(Refer to 9-4.)
Do you hear the expansion valve "click,
click·······"?
Do you feel the expansion valve vibrate
on touching it ?
Turn ON the power supply.
<Preparation of the remote controller>
While pressing both OPERATION SELECT button
and TOO COOL button on the remote controller at the
same time, press RESET button.
First, release RESET button.
And release the other two buttons after all LCD except
the set temperature in operation display section of the
remote controller is displayed after 3 seconds.
Yes
No
No
Yes
No
Yes
Yes
MUZ-GC25/35NA MUZ-GC50NA-
C2