Low
28i on Worcester Bosch 24i Junior

This code is not a fault; it is an informational status message indicating that your boiler is performing its standard self-check procedure ten minutes after ignition.

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

NOMINAL BOILER RATINGS (10 Minutes After Lighting) BOILER ADJUSTED FOR G20 (Natural Gas)

From this model's manual
Verified against the Worcester Bosch 24i Junior Rsf installation & service manual, page 2.
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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