Medium
F.86 on Vaillant ecoFIT Pure 830

Your boiler has lost the connection to your underfloor heating system, meaning it cannot properly communicate with or control the temperature of those specific rooms.

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

Underfloor heating contact fault

Engineer required

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

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Related fault codes

F.83View →F.84View →

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