High
E13 on Baxi Suprima 30

Your boiler has detected that a internal water flow sensor is stuck, meaning the system cannot correctly tell if water is moving before it starts the burner.

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 →

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