Remote controller cannot communicate with the heater; display shows H11 or communication error.

Electrical safety: Turn OFF power before working on wiring. Do not short communication terminals.

• 1. Check remote cable connections:
  • Ensure the remote controller cable is firmly plugged into the heater's terminal block.
  • Verify the connector at the remote controller is secure.
• 2. Inspect cable for damage:
  • Look for cuts, pinches, or crushed sections along the cable route.
  • Replace the cable if any damage is found.
• 3. Verify polarity:
  • Some Panasonic models require correct polarity on the remote terminals (e.g., + and –). Check the installation manual and correct any reversed connections.
• 4. Test with a short cable:
  • If possible, connect the remote directly at the heater with a short known‑good cable to rule out wiring issues in the wall.
• 5. Replace remote controller: If wiring is good but H11 persists, the remote controller PCB may be faulty and should be replaced with a genuine Panasonic unit.