High
A41 on Ferroli Optima 201

Your boiler has lost its connection to the component that monitors water flow, meaning it cannot safely trigger the heating or hot water to start.

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

Flow sensor disconnected

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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