High
OVERHEAT LOCKOUT on Baxi Solo 3 40 PF

Your boiler has switched itself off because it has reached a temperature that is too high to operate safely.

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

Lights: Off / On / On (Flash / Off / On). Flow temperature > 60° C or fan temperature > 60° C, or faulty thermostats/thermistor.

From this model's manual
Verified against the Baxi Solo 2 installation & service manual, page 52.
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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