Service Manual

Servicing Items to be Confirmed SiUS281811E
166 Part 6 Service Diagnosis
1. Servicing Items to be Confirmed
1.1 Troubleshooting
(1) Initial verification and troubleshooting
1. Properly understand the end user's needs and issues.
2. Check the cause of errors according to the description provided by the end user.
3. Check if the remote controller displays any error codes.
(Or use the outdoor unit monitoring mode to check for errors).
4. If there is no display of error codes, refer to Symptom-based Troubleshooting on page 169
for diagnosis.
If an error code is displayed, refer to troubleshooting flowchart for diagnosis.
(2) Take appropriate measures.
1. Repair the defect or replace the parts according to the troubleshooting results.
2. Turn off the power supply for 10 minutes before disassembling.
3. The refrigerant has to be collected before refrigerant system components are replaced.
(3) Verification after taking appropriate measures
1. Run the unit after repairing the defect to confirm normal unit operation.
2. Record the check results and inform the client.
1.2 Precautions for Maintenance
Pay attention to the following matters in servicing.
(1) Precaution for maintenance
Touch the paint-free metal part of the product (electrical box lid of the standard model; tap bolts of
electrical box of anti-corrosion and heavy anti-corrosion models) to release static electricity before
starting work.
(2) Precautions for maintaining the service cover
After maintenance, make sure to close the service cover.
(Otherwise, leakage of water or contamination by foreign matter may cause defects)
(3) Precautions for maintaining the electrical box
1. Turn off the power for 10 minutes before opening the cover of the electrical box.
2. After opening the cover, use the tester to measure the terminal voltage of the power supply
terminal to make sure that the power has been cut.
Then check if the circuit capacitor voltage is under 50 VDC.
3. To avoid PCB defects, touch the earth terminal of the electrical box with your hand when
unplugging the connector to release static electricity.
4. Unplug the connectors X106A and X107A (30/36/42/48 class models only), of the outdoor fan
motor.
When unplugging the connectors, do not touch the live parts.
(When the outdoor fan is rotating because of strong wind, there is a risk of electric shock due to
main circuit board capacitor power storage.)
5. After maintenance, reconnect the connectors of the outdoor fan in their original positions.
 Otherwise, the remote controller will display error code E7, preventing normal operation.