Low
G20 on Main Eco Compact Combi

Your boiler is displaying a setting notification indicating that it is configured to run on natural gas, which is the standard fuel type for UK homes.

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 Main Eco Compact Combi installation & service manual, page 12.
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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