High Lockout
12 on Glow-worm Xtramax HE

Your boiler's control panel has likely detected moisture or dampness inside the screen or buttons, preventing it from working correctly.

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

USER INTERFACE: INTERFACE MAY BE DAMP. DRY IT OUT OR REPLACE.

What causes this fault?

This fault occurs when the boiler's control panel detects moisture or condensation within the electrical circuits of the display screen. The most common reason is water ingress from a leak elsewhere in the boiler or high humidity causing dampness behind the buttons. When this happens, the interface becomes unresponsive to prevent a short circuit, resulting in a system shutdown.

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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Related fault codes

F11View →F13View →F14View →

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