High
Lockout light on Baxi Solo 3 40 PF

Your boiler has shut down because it has detected an unsafe temperature or a component failure in the pilot light system.

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

Boiler has overheated / No continuity across overheat thermostat / Continuity across sensor / Pilot solenoid failure

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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