High
Lights Off Off Off on Baxi Solo 3

Your boiler is not receiving the signal to turn on, which usually means your external heating controls like the thermostat or programmer are not calling for heat.

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

No Switched Live to boiler. Check Systems Controls and System Wiring.

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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