Medium
F86 on Heatline Monza

Your boiler has detected an issue with the connection to your underfloor heating system, which prevents the boiler from communicating correctly with that circuit.

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

Underfl oor heating contact fault

Engineer required

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

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