High
Connection on Glow-worm Energy System

Your boiler's electronic control panel is having trouble talking to the main brain of the unit, which means it cannot register your settings or operate 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.

What the manual says

Manufacturer manual

No communication between the PCB and the user interface

From this model's manual
Verified against the Glow Worm Energy System installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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