Troubleshooting - Mitsubishi Electric PUHZ-W50VHA Service Manual

8

TROUBLESHOOTING

8-1. 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 control board of outdoor unit. Actions to be taken for service,
which depends on whether or not the trouble is reoccurring at service, are summarized in the table below. Check the contents
below before investigating details.
Unit conditions at service
The trouble is reoccurring.
The trouble is not reoccurring.
8-2. CHECK POINT UNDER TEST RUN
Before test run
• After installation of outdoor units, piping work and electric wiring work, re-check that there is no water leakage, loosened con-
nections and incorrect polarity.
• Measure impedance between the ground and the power supply terminal block (L, N) on the outdoor unit by 500 V Megger
and check that it is 1.0 M or over.
• Turn on power supply 12 hours before test run in order to protect compressor.
• Make sure to read operation manual before test run. (Especially items to secure safety.)
Error code
Judge what is wrong and take a corrective action according
Displayed
to "8-3. Self-diagnosis action table".
Conduct troubleshooting and ascertain the cause of the
Not displayed
trouble.
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
trouble occurred, matters related to wiring
Logged
and etc.
Reset error code logs and restart the unit after finishing
service.
There is no abnormality in electrical component,
controller board, and etc.
Re-check the abnormal symptom.
Conduct troubleshooting and ascertain the cause of the
trouble.
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, and etc.
21
Actions to be taken for service (summary)