Mitsubishi Electric PUY-A12NKA7, Service Manual

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10 TROUBLESHOOTING
<Check code displayed by self-diagnosis and actions to be taken for service (summary)>
Present and past check codes are logged, and they can be displayed on the wired remote controller and control board of out-
door unit. Actions to be taken for service, which depends on whether or not the trouble is reoccurring in the field, are summa-
rized in the table below. Check the contents below before investigating details.
10-1. TROUBLESHOOTING
Unit conditions at service
Check code Actions to be taken for service (summary)
The trouble is reoccurring.
Displayed
Not displayed
Judge what is wrong and take a corrective action according
to “10-4. SELF-DIAGNOSIS ACTION TABLE”.
Conduct trouble shooting and ascertain the cause of the
trouble according to “10-5. TROUBLESHOOTING OF
PROBLEMS”.
The trouble is not reoccurring.
Logged
Not logged
1
Consider the temporary defects such as the work of
protection devices in the refrigerant circuit including
compressor, poor connection of wiring, noise , etc.
Re-check the symptom, and check the installation
environment, refrigerant amount, weather when the
trouble occurred, matters related to wiring, etc.
2
Reset check code logs and restart the unit after finishing
service.
3
There is no abnormality concerning of parts such as
electrical component, controller board, remote controller,
etc.
1
Re-check the abnormal symptom.
2
Conduct troubleshooting and ascertain the cause of the
trouble according to “10-5. TROUBLESHOOTING OF
PROBLEMS”.
3
Continue to operate unit for the time being if the cause
is not ascertained.
4
There is no abnormality concerning of parts such as
electrical component, controller board, remote controller,
etc.
10-2. CHECK POINT UNDER TEST RUN
(1) Before test run
• After installation of indoor and outdoor units, piping work and electric wiring work, re-check that there is no refrigerant leak-
age, loosened connections and incorrect polarity.
• Measure impedance between the ground and the power supply terminal block (L1, L2) on the outdoor unit by 500V Megger
and check that it is 1.0M
"
or over.
Note: Do not use 500V Megger to indoor/outdoor connecting wire terminal block (S1, S2, S3) and remote controller terminal
block (1, 2). This may cause malfunction.
• Make sure that test run switch (SW4) is set to OFF before turning on power supply.
• Turn on power supply 12 hours before test run in order to protect compressor.
• For specific models which requires higher ceiling settings or auto-recovery feature from power failure, make proper changes
of settings referring to the description of “12. FUNCTION SETTING”.
Make sure to read operation manual before test run. (Especially items to secure safety.)
OCH636A