High Lockout
Neon 1 NOT lit on Glow-worm Space Saver

Your boiler appears to have no power reaching it, which is likely caused by an external electrical issue or a blown fuse inside the unit.

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

Fault with mains supply or PCB fuse.

What causes this fault?

This fault occurs when the electrical circuit feeding the boiler is broken, meaning the unit cannot receive the power it needs to operate. The most common reason is a blown fuse within the boiler's internal control board or an issue with the external power switch on the wall. In some cases, a power surge or a failing internal component can cause the fuse to pop as a safety precaution to protect the sensitive electronics.

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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Neon 2 NOT litView →

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