High
Lockout light on on Baxi Solo 3 40 PF

Your boiler has likely stopped working because it reached a temperature that is too high, causing it to shut down 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

This can occur if the boiler has overheated. Reset by turning control knob OFF, wait 10 seconds then turn ON. Check continuity across the overheat thermostat.

From this model's manual
This code was read directly from the manufacturer service manual for this model.
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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All 23 fault codes on the Solo 3 40 PF

Seeing a different code? Every code this model can display, in one place.

Boiler On (Orange LED)Boiler On light onBurner LED GreenBurner On light offFan/Flue LED GreenIndicator light inside box litLights: Flash Flash OnLights: Flash Off FlashLights: Flash Off OnLights: On Off FlashLights: On Off OnLights: On On OnOverheat (Red LED)Overheat indicator lightOverheat Neon IlluminationPeripheral / Pump LED GreenPilot On lightPilot On light onPilot/Ignition LED GreenPower LED GreenPower On (Green LED)Red neon illuminated

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