Medium Warning
54:2 on Viessmann Vitodens 200-W

Your boiler is having trouble communicating with the solar heating control module during its automatic setup process.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

With Vitosolic 200 (automatical adjustment on recognition)

What causes this fault?

This fault occurs when the boiler's main control unit tries to automatically detect and link up with your solar thermal heating system but fails to receive a response. The most common reasons are a loose connection in the communication wiring, a blown fuse in the solar module, or a malfunction within the Vitosolic control box itself.

Engineer required

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

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Related fault codes

54:1View →F4View →

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