Mitsubishi Electric MR-FT35EH-SW-C, Service Manual

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Tens'
place
Ones'
place
3 4
5 0
5 1
5 2
5 3
5 5
5 6
5 7
The setting of Self Mode Check will be displayed and blinks during or Self Mode Check operation.
SHORT or OPEN circuit of thermister.
When the resistance is
∞ Ω
, the circuit is deemed open-circuited.
When the resistance is 0
Ω
, the circuit is deemed short-circuited.
The error codes E50 to E55are not displayed even if those abnormalities occur when power is turned on.
Therefore, be sure to perform self check mode operation in order to check if any abnormality
indicated by these error codes occurs.
If those errors still continue for 1 minute after the restart, E56 will be displayed again. (NOTE4)
(NOTE5)
(NOTE1)
(NOTE2)
Inverter drive module
abnormality The overcurrent error is detected before
starting the compressor (failure of the IC
in the inverter drive module) >Replace
the control board. An attempt to restart the compressor is
repeated every 3 minutes
Trouble of control board
(EEPROM related trouble)
(NOTE4)
EEPROM (IC11M)
accumulates data necessary for control.
• The data are not input accurately.
• The microcomputer cannot read the
data. >Replace the
control board. If abnormality occurs when power is
turned on, the compressor is stopped
for 10 minutes.
When abnormality occurs during
normal operation, the compressor
keeps operating.
Defective wiring
connecting or trouble of
control board The errors E50 to E53 keep occurring
over one and a half hour. (The situation,
which compressor cannot be operated,
continues.) • The error display starts after
the error is determined as E56.
• The error display continues
until defrosting starts or cooling
operation gets back to normal. (The
error display does not disappear by
unplugging and plugging the power
cord.)
(Note5)
• An attempt to restart the compressor
is repeated every 3 minutes.
Trouble of bus-bar voltage • The range of bus-bar voltage is not
approx. 50 ~ 340 VDC
Trouble of inverter
software reset function • The inverter driving software
malfunctions.
Trouble of startup,
synchronization or
overcurrent detection
(NOTE4)
• There is no current at compressor
startup.
• The phase current exceeds 5.5 A at
compressor startup.
• The phase current exceeds 3.3 A
during compressor operation.
•A current of 5.3 A or more runs into the
bus-bar of control board.
The compressor is stopped and
reactivated 10 minutes later
Refer to “Compressor does not operate” topic
Refer to “Compressor does not operate” topic
Clogging of refrigerant
pipe or trouble relatedto
compressor. (T0: Defrost thermistor temperature at
power input, T1: Defrost thermistor
temperature when 15 minutes have
passed from the power input)
• When the difference between T0 and
T1 is T0
≦
T1
Check the compressor and the pipe. When cooling operation returns to
normal condition, the display of error
code disappears.
Trouble of inverter circuit
(NOTE4) • There is any trouble in the circuit
which detects current of compressor >Replace the
control board.
ERROR CODE
Trouble Detecting method Check point How to fix Control
16