High
H.01 – .08 on Baxi Suprima 50

Your boiler is overheating or water is not moving through the system quickly enough to be cooled down.

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

Sensor fault, flow temperature increasing too fast in heating mode or insufficient circulation.

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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