Boiler Fault Code 7E:1

Also written as 7E1 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026

Fault code 7E:1 appears across 1 boiler brand and 5 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler system is communicating with multiple other boilers through a shared exhaust pipe, and it has detected a technical configuration error in that connection. (As reported on Viessmann Vitodens 200)