Low
P3 on British Gas RD 430i

Your boiler is simply performing a routine internal check-up as part of its startup sequence.

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

Please wait, initialisation in progress.

Shared across the RD 430i 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 32 fault codes on the RD 430i

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

-II-0.02.02.42.52.75.07.030405060708090100A1b1C1C4C6d3E2E9EAF7FAFCFdP1P2

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