Mitsubishi Electronics MSZ-GA35VA, MSZ-GA25VA, MSZ-GA22VA Instruction of troubleshooting

9-3. Instruction of troubleshooting

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Indoor unit operates. Outdoor unit doesn't operate.

Indoor unit operates. Outdoor unit doesn't operate normally.

Indoor unit doesn't receive the signal from remote controller.

OPERATION INDICATOR lamp on the indoor unit is flashing on and off.

Outdoor unit		Outdoor unit
operates in		doesn't
only Test Run		operate
operation.		even in
	w1	Test Run
		operation.
			w1

Check room	Refer to
temperature	"How to check
thermistor.	inverter/
Refer to 9-7.	compressor".
"Test point
diagram and
voltage".

Unit doesn't	Indoor unit
	operates, when
operate
	EMERGENCY
normal
	OPERATION
operation in
	switch is pressed.
COOL or
HEAT mode.

Refer to	Refer to 9-6.B
"Check of	"Check of
R.V. coil".	remote controller
	and receiver
	P.C. board".

Indoor unit doesn't operate, when

EMERGENCY

OPERATION switch is pressed.

1.Check indoor / outdoor connecting wire. (Check if the power is supplied to the indoor unit.)

2.Refer to 9-6.C"Check of indoor electronic control P.C. board and indoor fan motor".

If blinking of OPERATION INDICATOR lamp cannot be checked, it can be checked with failure mode recall function.

w1

"Test Run operation" means the operation within 30 minutes after EMERGNCY OPERATION switch is pressed.

As for outdoor unit MUZ type, refer to service manual OB379. As for outdoor unit MXZ type, refer to service manual OB377.

All lamps	Left lamp	Left lamp
	Flash on and off	2-time flash
Flash on and off
	at 0.5-second	Cause:
at 0.5-second
intervals	intervals	Indoor unit
Cause:	Cause:	• Trouble of
Indoor unit	Indoor/	room temp-
• The horizontal	Outdoor unit	erature/
vane is not	• Mis-wiring	indoor coil
installed	or trouble	thermistor
correctly.	of serial signal
Refer to 9-6.	Refer to 9-6.	Check room
E "Check of	D "How to	temperature
installation of	check of	thermistor
the horizontal	mis-wiring	and indoor
vane".	and serial	coil thermis-
	signal error	tor.
	(when	Refer to 9-7.
	outdoor unit	"Test point
	doesn't work)".	diagram and
		voltage".

Left lamp	Left lamp	Left lamp	Left lamp	Left lamp	Left lamp
3-time flash	4-time flash	5-time flash	6-time flash	7-time flash	14-time flash
Cause:	Cause:	Cause:	Cause:	Cause:	Cause:
Indoor unit	Indoor unit	Outdoor unit	Outdoor unit	Outdoor unit	Outdoor unit
• Trouble of	• Trouble of	• Outdoor	• Trouble of	• Trouble of	• Other
indoor fan	indoor unit	power	thermistor	outdoor	abnormality
motor	control	system	in outdoor	control
	system	abnormality	unit	system

Refer to 9-6.	Replace the	Refer to	Refer to	Replace the	Check
A "Check of	indoor	"How to check	"Check of	inverter P.C.	"Flow chart of
indoor fan	electronic	inverter/	outdoor	board or	the detailed
motor".	control	compressor".	thermistors".	the outdoor	outdoor unit
	P.C. board.			electronic	failure mode
				control P.C.	recall function."
				board.

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