Medium
G20 on Sime Ecomfort Plus HE

Your boiler is displaying a technical configuration code indicating it is calibrating or checking the gas pressure supply to the burner.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Gas G20 (Burner Modulator max. pressure mbar)

From this model's manual
Verified against the Sime Ecomfort Plus He Combi installation & service manual, page 21.
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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Related fault codes

G25View →A01View →

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