High
Faulty modulation gas valve on Biasi Riva Compact HE M96a

Your boiler is unable to control the flow of gas correctly, which means it cannot fire up to provide heating or hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Faulty on-off operators or not electrically supplied.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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