High
H.02 – .06 on Baxi Suprima 40

Your boiler has detected that the water pressure is too low or there is a leak somewhere in your heating system, causing it to stop working as a safety precaution.

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

Temporary error caused by system water pressure, water leak on boiler, water leak on system.

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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