High
H.01 – .18 on Baxi Suprima 50

Your boiler has detected that water isn't moving through the system properly or a sensor is getting a strange temperature reading, so it has shut down to prevent overheating.

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

No water circulation, insufficient circulation or sensor error.

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 →E125View →E117View →

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