Low
G20 on Glow-worm Flexicom CXi

Your boiler is displaying a code indicating it is set up to run on natural gas, but it does not represent a physical fault with the machine itself.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Natural Gas (G20)

From this model's manual
Verified against the Glow Worm Flexicom Cxi 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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