Baxi 430 COMBI 2.1 Fault codes & diagnostics

1 fault code with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.

Combi Gas 2024-present
GC Number 47-077-75
Download the Baxi 430 COMBI 2.1 manualThe official installation and service manual (PDF), the document these fault codes were read from. PDF

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Versions & GC numbers

Which version do you have?

The GC number on your boiler's data badge identifies the exact appliance and production years, as recorded in the UK Product Characteristics Database.

GC number Appliance (register name) Produced
47-077-75 430 COMBI 2.1 2024–present

Appliance names and production years are taken from the UK Product Characteristics Database (the SAP/SEDBUK register). Where a GC number is also printed in this model's own manufacturer manual, both sources were checked to agree.

Fault codes

All 1 documented codes

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254

Your boiler has detected a thermostat or room controller attached to it that is not made by Baxi, preventing the heating system from working properly.

High Engineer only £90-180

Parts commonly replaced

  • Baxi compatible room thermostat
  • Wiring centre

Related codes

Full explanation for 254
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