Mitsubishi Electric MSZ-AY25VG-ET1 Service Manual page 32

4. Table of indoor unit failure mode recall function
NOTE: Blinking patterns of this mode differ from the ones of TROUBLESHOOTING CHECK TABLE (10-4.).
The upper lamp of
Abnormal point
OPERATION
(Failure mode)
INDICATOR lamp
Not lit Normal
1-time blink every Room temperature
0.5-second
thermistor
2-time blink Indoor coil
2.5-second OFF
thermistor
3-time blink
Serial signal
2.5-second OFF
11-time blink
Indoor fan motor
2.5-second OFF
12-time blink Indoor control
2.5-second OFF
system
5. Table of indoor unit failure mode recall function (When recalled at a set temperature of 23°C)
Table of AIR PURIFYING power failure mode recall function
Abnormal point
POWER lamp
(Failure mode)
AIR PURIFYING
1-time blink
power control
Electrode
2-time blink
(Spark discharge)
Electrode
(
Abnormal electric
3-time blink
discharge error 1
Electrode
(
Abnormal electric
4-time blink
discharge error 2
AIR PURIFYING
5-time blink
power
NOTE1 : Blinking patterns of this mode differ from the ones of TROUBLESHOOTING CHECK TABLE (10-4.).
NOTE2 : As soon as an abnormality is detected, AIR PURIFYING power goes OFF, therefore measuring instrument which
records the voltage wave is required in order to perform the above mentioned voltage measurement.
OBH932
Condition
—
The room temperature thermistor short or
open circuit is detected every 8 seconds dur-
ing operation.
The indoor coil thermistor short or open circuit
is detected every 8 seconds during operation.
The serial signal from outdoor unit is not
received for a maximum of 6 minutes.
The rotational frequency feedback signal is not
emitted for 12 seconds after the indoor fan
motor is operated.
It cannot properly read data in the nonvolatile
memory of the indoor electronic control P.C.
board.
Condition
When AIR PURIFYING power cannot be turned OFF
even if the AIR PURIFYING operation is turned OFF
with the remote controller.
When the voltage between CN1T1
on the electronic P.C. board falls below 1.3V
(spark discharge judgment voltage).
When the voltage between CN1T1
)
on the electronic P.C. board falls by 1.2V below
the normal voltage value (2.5V).
When the voltage between CN1T1
)
on the electronic P.C. board falls significantly.
(0.4V / 0.5ms)
When the voltage between CN1T1
on the electronic P.C. board rises above 3V.
Refer to the characteristics of the room temperature
thermistor (10-7.).
Refer to the characteristics of the main indoor coil
thermistor, the sub indoor coil thermistor (10-7.).
Refer to 10-6.
signal error".
Refer to 10-6.
Replace the indoor electronic control P.C. board.
(+) and (GND)
(+) and (GND)
Refer to 10-6.
(+) and (GND)
(+) and (GND)
32
Remedy
—
"How to check miswiring and serial
"Check of indoor fan motor".
Remedy
"Check of AIR PURIFYING power".