Sinclair SCV-750EB Service Manual page 85

5.8 EC Troubleshooting
Digital display output
Description
EC indicates that the number of slave units detected by master unit has decreased.

All units stop running.

Error code is only displayed on the user interface.
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Possible causes
Some outdoor units power off.

Power supply abnormal.
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Incorrect outdoor unit address setting.
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Communication wires between outdoor units not connected properly.
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Wiring connection is loosen.
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Damaged main PCB or electric control box communication terminals block.

Procedure
Some outdoor units in the system are
The power supply is abnormal
Troubleshoot as for an E2 error
Notes:
1. For SCV-750EB and SCV-1400EB, check digital display on the main PCB. If digital display is on, the main PCB is powered on, if digital display is off, the main
PCB is powered off. Please refer to labeled 11 in Part 4, 2.7 Slave PCB component.
2. For SCV-900EB and SCV-1800EB, check digital display on the main PCB. If digital display is on, the main PCB is powered on, if digital display is off, the main
PCB is powered off. Please refer to labeled 37 in Part 4, 2.2.1 Main PCB component.
3. See Part 4, 4.4 "E2 Troubleshooting".
EC
powered off 1
No
No
2
Yes
Power on all the outdoor units
Yes
Check the power supply equipment
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