High Lockout
20 on Glow-worm Ci Plus

Your boiler's main control panel is failing to communicate with the internal system because they are not compatible or there is a software mismatch.

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 not compatible with boiler

What causes this fault?

This fault occurs when the boiler's internal computer and the front display panel are unable to talk to each other correctly. It most commonly happens after a repair where a replacement part has been installed that doesn't match the specific software version of your boiler, or if a component has suffered an electrical surge.

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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