High Lockout
FLASH OFF FLASH on Baxi Solo

Your boiler is not receiving enough electrical power from the main supply 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.

Technical description

Voltage less than 180V

What causes this fault?

This fault occurs when the electrical supply entering the boiler drops to a level where the electronic components can no longer function safely. It is usually caused by a wider problem with the local power grid or a failing main circuit board that can no longer process the incoming voltage correctly. In some cases, loose wiring or a faulty external socket can also cause this dip in electrical pressure.

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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