High
18 on Glow-worm 18si

Your boiler's control panel has lost communication with the main computer, meaning you cannot adjust settings or operate 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.

What the manual says

Manufacturer manual

Local user interface fault

From this model's manual
Verified against the Glow Worm Ci Range installation & service manual, page 34.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the display panel on the front of your boiler can no longer 'talk' to the main internal computer. The most common reason is a loose or damaged connection cable inside the unit, or a components failure on one of the electronic circuit boards. Because the brain of the boiler cannot receive commands from the buttons, the system shuts down as a safety precaution.

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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