Indoor/outdoor unit communication error (Indoor unit receiving)

What does E6 mean?

The indoor controller board fails to receive signals normally for 6 minutes after power-on, or 10 minutes during operation, or from the outdoor board in twin systems. This points to communication wire contact failure, short circuits, miswiring, noise, or defects in communication circuits or fan motor/rush current resistor. It severely impairs the indoor unit's ability to coordinate with the outdoor unit.

Complete Troubleshooting Guide

1. 1

   Inspect the indoor/outdoor unit connecting wire for disconnections, looseness, short circuits, or incorrect wiring (polarity), checking all units in twin systems.

2. 2

   Cycle the power off and on. If the error recurs, proceed with further diagnostics.

3. 3

   Detach the fan motor connector (CNF1, 2) and re-power; if the error clears, replace the fan motor. Otherwise, replace the outdoor controller circuit board.

4. 4

   Use a tester to check resistor RS1 on the outdoor noise filter board; replace the board if it's open.

5. 5

   If other indoor controller boards exist in a twin system, consider they might be defective.