High
E125 on Potterton Suprima HE

Your boiler is struggling to move heat away from its core, meaning the water isn't circulating properly to warm up your radiators or taps.

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 Fault or Primary Circulation Problem (Within 15 seconds of the burner lighting the boiler temperature has not changed by 1° or within 10 minutes of the burner lighting the boiler temperature twice exceeds the selected temperature by 30°)

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

E110View →E119View →

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