Low
24i on Worcester Bosch 24i / 28i Junior

This code is not actually an error; it is a status indicator showing the boiler is performing a routine performance check 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)

Shared across the 24i / 28i Junior range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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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All 27 fault codes on the 24i / 28i Junior

Seeing a different code? Every code this model can display, in one place.

28i200203208265AA1A8BCDEFF1F2Flash once per secondGHILight onNo CH function (DHW OK)No DHW function (CH OK)No lights and no functions (with demand)rET1T3

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