High
No Pump Feed on Potterton Promax 15 & 24

Your boiler has detected a safety issue preventing it from circulating heart or hot water, and it has shut down to protect itself.

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

Safety thermostat open circuit, fan protection thermostat open circuit, flow thermistor out of resistance range, or blocked condensate trap.

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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