Mitsubishi Electric MSZ-WR NA Series, Service Manual

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30
OPERATION
INDICATOR
upper lamp
(Indoor unit)
Abnormal point
(Failure mode / protection)
LED indication
(Outdoor P.C. board)
Condition Remedy
Indoor/
outdoor unit
failure mode
recall function
Outdoor unit
failure mode
recall function
11-time blink
2.5 seconds
OFF DC voltage 8-time blink
2.5 seconds OFF DC voltage of inverter cannot be
detected normally.
• Refer to 10-5. "How
to check inverter/
compressor".
—
○
Each phase current of
compressor 9-time blink
2.5 seconds OFF Each phase current of compressor
cannot be detected normally.
12-time blink
2.5 seconds
OFF Overcurrent Compressor open-
phase 10-time blink
2.5 seconds OFF Large current fl ows into intelligent
power module (IPM)/power module
(IPM) 1.
The open-phase operation of
compressor is detected.
The interphase short circuit occurs
in the output of the intelligent power
module (IPM)/power module (IPM) 1.
The compressor winding shorts circuit.
• Reconnect compressor
connector.
• Refer to 10-5. "How
to check inverter/
compressor".
—
○
14-time blink
2.5 seconds
OFF Stop valve (Closed valve) 14-time blink
2.5 seconds OFF Closed valve is detected by compressor
current.
• Check the stop valve
○ ○
4-way valve/
Pipe temperature 16-time blink
2.5 seconds OFF The 4-way valve does not work
properly.
The indoor coil thermistor detects an
abnormal temperature.
• Check the 4-way valve.
• Replace the inverter
P.C. board.
Outdoor refrigerant
system abnormality (
MUZ-
WR09/12NA )
1-time blink
2.5 seconds OFF A closed valve and air trapped in the
refrigerant circuit are detected based on
the temperature sensed by the indoor
and outdoor thermistors and the current
of the compressor.
• Check for a gas leak
in a connecting piping
etc.
• Check the stop valve.
• Refer to 10-5.
“Check of outdoor
refrigerant circuit”.
○ ○
NOTE: Blinking patterns of this mode differ from the ones of
TROUBLESHOOTING CHECK TABLE (10-3.).
OBH819A