High
09 on Glow-worm EnergySaver Combi

Your boiler's main electronic brain has encountered an internal error and cannot communicate properly with the rest of the system, meaning the boiler has shut down for safety.

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

There is an internal fault in the Automatic Control Module.

From this model's manual
Verified against the Glow Worm Energysaver Combi 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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