High
A42 on Ferroli iBoiler 24

Your boiler is struggling to accurately measure how much water is moving through the system, which is preventing it from heating up correctly.

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 error – sensor damaged

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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Related fault codes

F43View →A03View →F05View →

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