High Lockout
All LEDs Off on Vokera Option

Your boiler has lost all power and is completely unresponsive, meaning it is currently unable to provide heating or hot water.

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 power, blown fuse, Internal fault. Ensure power supply to Boiler is on, check fuse, Contact engineer

What causes this fault?

This fault occurs when the boiler's electrical circuit is broken, preventing the control system from turning on. The most common reason is a blown 3A fuse in the wall spur or on the internal board, often triggered by a power surge or a failing internal component causing short circuit.

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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