High
Red neon illuminated on Baxi Solo 3 40 PF

Your boiler has detected that it is getting too hot and has automatically switched itself off to prevent damage.

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.

What the manual says

Manufacturer manual

Indicates that the overheat cut-off device has operated.

From this model's manual
Verified against the Baxi Boiler Solo 3 80 Pf System installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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