High
P 3.1 or higher on Potterton Powermax HE

Your boiler has detected that the water pressure inside the system is dangerously high while it is running, which can put unnecessary stress on your pipework and internal components.

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

Pressure indicated at normal working temperatures (80 °C) is too high

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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