Medium
E77 on Biasi Antares System

Your boiler's control system is struggling to adjust the flame size correctly, which may lead to inefficient heating or the unit shutting down.

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

System out modulator control parameters.

Engineer required

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

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Related fault codes

E07View →E08View →E21View →

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