Medium
F6 on Heatline Vizo Plus

Your boiler's outside temperature sensor is broken or sending an incorrect signal, which means the system doesn't know how hard it needs to work to heat your home.

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

External sensor fault (where fitted)

Engineer required

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

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Related fault codes

F1View →F2View →F4View →

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