E83-87 — Communication error with room unit

What does E83-87 mean?

The boiler is unable to communicate correctly with the room thermostat or other room control units.

• Loose or damaged cable connection between the room unit and the boiler's main control board (PCB).
• Problem with the RF (wireless) link for wireless room units.
• Faulty room unit or boiler PCB.

Click steps to track your progress.

1. 1

   Check the batteries in your room thermostat or room control unit if it's wireless.

2. 2

   Ensure the room unit is within range and not obstructed by large metal objects if it's wireless.

3. 3

   A qualified technician should check the communication cable or RF link between the room unit and the boiler.