High
No Water Flow on Baxi System

Your boiler is struggling to detect water moving through the system, causing it to continuously turn itself on and off to protect against overheating.

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

Indicated by the flow switch - a continuous cycle of Pump Overrun and Anti-cycle occurs.

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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