Medium
F.86 on Vaillant ecoTEC plus Regular

Your boiler has lost the connection to your underfloor heating system, meaning it doesn't know when to start or stop heating 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.85View →F.87View →

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