Troubleshooting - Mitsubishi Electric EHPT17X-VM2E Service Manual

10

TROUBLESHOOTING

10-1. Troubleshooting
<Summary of self-diagnosis based on Check codes and Service Procedures>
Present and past Check codes are logged, and they can be displayed on the main remote controller or control board of the outdoor unit.
Please refer to the table below and subsequent explanations to diagnose and remedy typical problems that may occur in the field.
Unit Condition
Reoccurring problem
Non reoccurring problem
Note:
Electrical components should only be replaced as a final option. Please follow instructions in "10-4. Self-diagnosis and action" and "10-5. Troubleshoot-
ing by inferior phenomena" fully before resorting to replacing parts.
10-2. Test Run
Before a test run
• After installation of outdoor unit, pipework and electrical wiring, recheck that there is no water leakage, loosened connections or miswiring.
• Measure impedance between the ground and the power supply terminal block (L,N) on the outdoor and indoor units with suitable (500V) ohmmeter. Resistance
should be ≥ 1.0MΩ .
• Read the Installation and Operation Manuals fully especially the safety requirements before carrying out any test runs.
10-3. Malfunction diagnosis method by main remote controller
If during start up or operation a malfunction occurs, the check code screen may be displayed on the main remote controller.
The check code screen shows the following; code, unit, ref. address, and telephone number of installer (only if previously entered by the installer)
Please note in the case of some malfunctions as check code is not generated please refer to table "10-5. Troubleshooting by inferior phenomena" for more details.
To reset
1. To reset the main remote controller press "RESET" button.
2. Then press "Yes" button to confirm.
Code : L
Unit : FTC Address
Tel no. :
Code : L
Unit : FTC Address
Tel no. :
No
OCH814A
Check code Action
Displayed Use table "10-4. Self-diagnosis and action" to identify fault and correct.
Not Displayed Use table "10-5. Troubleshooting by inferior phenomena" to identify fault and correct.
Logged 1. Check temporary causes of defects such as the operation of safety devices on the refrigerant/water cir-
cuit including compressor, poor wiring, electrical noise, etc. Re-check the symptom and the installation
environment, refrigerant amount (Split systems only), weather conditions at time of fault, etc.
2. Reset Check code logs, Service the unit and restart system.
Not Logged
1. Recheck the abnormal symptom.
2. Identify cause of problem and take corrective action according to Table "10-5. Troubleshooting by inferior
phenomena".
3. If no obvious problem can be found, continue to operate the unit.
Error
:
Reset
Error
:
Reset error?
Yes
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