Medium
S.39 on Vaillant Turbomax Plus 828 E

Your boiler has detected that the water in your underfloor heating circuit has become too hot and has automatically shut down to prevent damage to your flooring.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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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

Contact thermostat has been activated (under floor systems)

Engineer required

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

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Related fault codes

S.30View →F.22View →

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