Check Of Lev (Expansion Valve) - Mitsubishi Electric SUZ-KA25VA Technical & Service Manual

Outdoor unit does not operate at all or stops immediately due to over current.
Check of current limiting resistor
K
When the current-limiting resistor is open, the rush current limiting relay (X64) may not work properly.
Does the current-limiting resistor
(R64A or R64B) on the power P.C.
board short out? (Normal
resistance : 5' ± 5% )
Yes
Replace the power P.C. board.
Check other electric parts in the main circuit together in the case of the defective current-limiting resistor.
Heating / Cooling does not work sufficiently.

Check of LEV (Expansion valve)

L
Turn ON the power supply.
< Preparation of the remote controller >
1 While pressing both OPERATION SELECT
button and TOO COOL button on the remote
controller at the same time, press RESET button.
2 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.
Press OPERATE/STOP(ON/OFF) button of the remote
controller (the set temperature is displayed) with the
remote controller headed towards the indoor unit. W 1
Expansion valve operates in
full-opening direction.
Do you hear the expansion
valve "click, click·······"?
Do you feel the expansion
valve vibrate on touching it ?
No
Is LEV properly fixed to the
expansion valve?
Yes
Does the resistance of LEV
have the characteristics?
(Refer to 12-4.)
No
Replace the LEV.
[SUZ-KA25VA.TH SUZ-KA35VA.TH SUZ-KA25VAH.TH SUZ-KA35VAH.TH]
Turn ON the power
No supply and press
EMERGENCY
OPERATION switch of
the indoor unit.
(For wireless remote controller use model)
Yes
Ok
No
Properly fix the LEV to the
expansion valve.
Measure each voltage between connector pins
of CN724 on the inverter P.C. board.
1.Pin3(-) Pin1(+)
Yes
2.Pin4(-) Pin1(+)
3.Pin5(-) Pin1(+)
4.Pin6(-) Pin1(+)
Is there about 3~5V AC between each?
NOTE: Measure the voltage by an analog tester.
Replace the
expansion valve.
Does LED on the inverter
P.C. board light up?
Yes
Does the rush current
limiting relay(X64) work
properly? (Normally it
close 1 minutes after
outdoor unit power ON.)
No
Replace the power P.C.board.
h
ON/OFF
TOO TOO
WARM COOL
NOTE : After check of LEV, do the undermentioned
No
Replace the
inverter P.C. board.
Yes
66
Replace the power P.C.
No
board or the inverter P.C.
board.
Yes
Replace the power P.C.
board or the compressor.
W 1. Regardless of normal or abnormal, a short
beep is emitted once as the signal is received.
operations.
1. Turn OFF the power supply and
turn ON again.
2. Press the RESET button on the remote
controller.