High
Lockout will not reset on Baxi 800 Heat (range)

Your boiler has detected that it is dangerously overheated or has run without enough water and will not restart until it has cooled down completely.

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 LOCKOUT RESET - Flow temperature remains > 60°C, fan ambient temperature > 90°C, or dry-fire lockout condition persists.

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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