High
neon flashing (Section B/C) on Potterton Performa 30 HE

Your boiler is struggling to push water around your heating system because the water pump is either stuck or blocked by trapped air.

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

Pump or Primary flow switch failure / Pump jammed or air in system

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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