High
E13 on Baxi 800

Your boiler has detected that a internal water valve is stuck in the 'on' position even though the pump has stopped, causing the system to shut down for safety.

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

Differential water flow switch fault (still closed).

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

E12View →E117View →E125View →

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