Indoor unit displays F11; operation may stop or be restricted.

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Possible Causes

Reversed or miswired communication cable, Loose terminal screws, Damaged interconnecting cable, Faulty indoor or outdoor PCB communication circuit

Safety first: Turn off power at the breaker before opening terminal covers.

Steps:

1. Verify wiring order: Confirm that terminals 1-2-3 (and earth) are wired identically between indoor and outdoor units.
2. Tighten terminals: Check all screws for tightness; loose connections can cause intermittent F11.
3. Inspect cable: Look for damage along the cable route, especially where it passes through walls or conduits.

If F11 continues after wiring checks, a technician should test the communication circuit and replace the faulty PCB.

Medium 3/5

Interconnecting Cable

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