High
H.01 – .18 on Baxi Suprima 80

Your boiler has likely stopped heating because water is not flowing through the system correctly or a temperature sensor has developed a fault.

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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