Troubleshooting; Check Point Under Test Run; Before Test Run - Mitsubishi Electric Mr.SLIM PU-P71VHA Service Manual

11

TROUBLESHOOTING

11-1. TROUBLESHOOTING
<Error code display by self-diagnosis and actions to be taken for service (summary)>
Present and past error codes are logged and displayed on the wired remote controller and control board of outdoor unit.
Actions to be taken for service, which depends on whether or not the inferior phenomenon is reoccurring at service, are sum-
marized in the table below. Check the contents below before investigating details.
Unit conditions at service
The inferior phenomenon is
reoccurring.
The inferior phenomenon is
not reoccurring.

11-2. 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 (L, N) on the outdoor unit by 500V Megger
and check that it is 1.0M" or over.
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.)
OC379F
Error code
Judge what is wrong and take a corrective action according
Displayed
to "11-4. Self-diagnosis action table".
Conduct trouble shooting and ascertain the cause of the
Not displayed
inferior phenomenon according to "11-5. Troubleshooting
of problems".
Consider the temporary defects such as the work of
protection devices in the refrigerant circuit including
compressor, poor connection of wiring, noise and etc.
Re-check the symptom, and check the installation
environment, refrigerant amount, weather when the
inferior phenomenon occurred, matters related to wiring
Logged
and etc.
Reset error code logs and restart the unit after finishing
service.
There is no abnormality concerning of parts such as
electrical component, controller board, remote controller
and etc.
Re-check the abnormal symptom.
Conduct trouble shooting and ascertain the cause of the
inferior phenomenon according to "11-5. Troubleshooting
of problems".
Not logged
Continue to operate unit for the time being if the cause
is not ascertained.
There is no abnormality concerning of parts such as
electrical component, controller board, remote controller
and etc.
30
Actions to be taken for service (summary)