High
A1 on Worcester Bosch 26 CDi Xtra

Your boiler has detected that there isn't enough water moving through the system, which is usually caused by a leak or a pump that has stopped working.

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

Water is leaking or the pump needs replacing or freeing due to the pump running dry.

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

E9View →

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