What does the Viessmann 7E:1 fault code mean?

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.

How much does it cost to fix Viessmann error code 7E:1?

Typical repair cost for the Viessmann 7E:1 fault is £120-250 including labour.

Viessmann 7E:1 Fault Code: What It Means & How to Fix It

Technical description

With flue gas cascade

What causes this fault?

This fault occurs when multiple boilers share a single chimney system and are failing to talk to each other correctly. It is usually caused by a poor wiring connection between the units or a conflict in the internal settings that tell each boiler which part it plays in the group. In some cases, a faulty electronic module or a blocked sensor in the exhaust pipe can also trigger this communication breakdown.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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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.

Technical description

What causes this fault?

Engineer required

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