1A8 E displayed — Bus communication error with TD 200 or heating appliance

What does 1A8 E mean?

The display on the RT10 or FW 100 control unit shows '1A8 E'. This indicates that the TD 200 or the main heating appliance, which communicate via the bus connection, are not responding.

• Defective bus connection.
• Interruption in the bus connection between devices.

Click steps to track your progress.

1. 1

   Check all bus connections to the TD 200 and the heating appliance to ensure they are secure.

2. 2

   Visually inspect the bus cables for any signs of damage or loose connections.

3. 3

   If the issue persists, contact a qualified technician to rectify any interruption in the bus connection or diagnose defective components.