Mitsubishi Electric MSZ-FA25VA Service Manual page 16

4. Indoor unit failure mode table
Abnormal point
POWER lamp
(Failure mode)
Not lighted Normal
Room temperature
1-time flash
thermistor
every 0.5-second
2-time flash
Indoor coil thermistor
2.5-second OFF
3-time flash
Serial signal
2.5-second OFF
11-time flash
Indoor fan motor
2.5-second OFF
12-time flash
Indoor control system
2.5-second OFF
NOTE : Blinking patterns of this mode differ from the ones of Troubleshooting check table (9-4.).
5. PLASMA DEODORIZING/PLASMA AIR PURIFYING power failure mode table
Abnormal point
POWER lamp
(Failure mode)
PLASMA DEODORIZING/
PLASMA AIR PURIFYING
1-time flash
power control
2-time flash Spark discharge
Abnormal electric
3-time flash
discharge error 1
Abnormal electric
4-time flash
discharge error 2
PLASMA DEODORIZING/
5-time flash
PLASMA AIR PURIFYING
power
NOTE1 : Blinking patterns of this mode differ from the ones of Troubleshooting check table (9-4.).
NOTE2 : As soon as an abnormality is detected, PLASMA DEODORIZING power and/or PLASMA AIR PURIFYING
power goes OFF, therefore measuring instrument which records the voltage wave is required in order to
perform the above mentioned voltage measurement.
Condition
–
When the room temperature thermistor
short or open circuit is detected every 8
seconds during operation.
When the indoor coil thermistor short or
open circuit is detected every 8 seconds
during operation.
When the serial signal from the outdoor unit is
not received for a maximum of 6 minutes.
When the rotational frequency feedback
signal is not emitted during the 12-seconds
indoor fan operation.
When it cannot properly read data in the
nonvolatile memory of the indoor electronic
control P.C. board.
Condition
When PLASMA DEODORIZING and/or
PLASMA AIR PURIFYING power cannot be
turned OFF even if the PLASMA operation is
turned OFF with the remote controller.
When the voltage between CN1 3(+)
and 2(GND) on the PLASMA POWER P.C.
board (in the PLASMA DEODORIZING or
PLASMA AIR PURIFYING unit) falls below
1.6V(spark discharge judgment voltage).
When the voltage between CN1 3(+)
and 2(GND) on the PLASMA POWER P.C.
board (in the PLASMA DEODORIZING or
PLASMA AIR PURIFYING unit) falls by 0.9V
below the normal voltage value (3V).
When the voltage between CN1 3(+)
and 2(GND) on the PLASMA POWER P.C.
board (in the PLASMA DEODORIZING or
PLASMA AIR PURIFYING unit) falls
significantly. (0.4V / 0.5ms)
When the voltage between CN1 3(+)
and 2(GND) on the PLASMA POWER P.C.
board (in the PLASMA DEODORIZING or
PLASMA AIR PURIFYING unit) rises above
the normal voltage value (3V).
16
Correspondence
–
Refer to the characteristics of the room
temperature thermistor (9-7.).
Refer to the characteristics of the main
indoor coil thermistor, the sub indoor coil
thermistor (9-7.).
Refer to 9-6.D "How to check mis-wiring
and serial signal error".
Refer to 9-6.A "Check of indoor fan
motor".
Replace the indoor electronic control
P.C. board.
Correspondence
Refer to 9-6.F"Check of PLASMA
DEODORIZING power" or 9-6.G"Check
of PLASMA AIR PURIFYING power".