High
Lockout on Baxi Solo 3 PFL

Your boiler has stopped working because it has detected a temperature that is too high and has temporarily disabled itself for safety.

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

Red light indicator - Can occur if the boiler has overheated; reset by turning control knob OFF, wait 10 seconds, then turn ON

From this model's manual
Verified against the Baxi Solo 3 Pfl 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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