High
E13 on Baxi Suprima 40

Your boiler is detecting that water is moving through the system even when the pump is supposed to be off, causing it 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

E10View →E12View →E28View →

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