High Lockout
12 on Glow-worm 30ci Plus

Your boiler is having trouble communicating with the control panel or your thermostat, meaning it cannot receive your instructions to turn on.

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 or distant control panel fault

What causes this fault?

This fault occurs when the main control board inside the boiler loses its electronic connection with the display panel or your room thermostat. The most common reason is a loose internal wiring connection or a failure in the circuit board that processes your commands, preventing the boiler from knowing when to fire up.

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

F13View →F14View →F15View →

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