17 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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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 |
|---|---|---|
| 41-470-59 | 624 SYSTEM 24 | 2018–present |
| 41-470-64 | 624 SYSTEM 24 LPG | 2018–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.
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Your boiler has lost communication with its internal electronic brain, causing it to shut down for safety.
Your boiler has lost communication with its main electronic brain, so it has safely shut down to prevent unexpected behaviour.
Your boiler has detected an internal temperature or sensor problem and has safely shut down to prevent overheating.
Your boiler has detected an internal communication or sensor issue and has safely shut down to prevent damage.
Your Baxi boiler has encountered a general system fault that requires professional technical diagnosis.
Your boiler has detected an internal electronic or flashing error and has safely locked itself out to prevent any issues.
Your Baxi boiler has temporarily stopped working because it has lost proper internal communication between its main electronic parts.
Your boiler has detected that the water pressure inside the heating system has dropped too low.
Your boiler has detected that water is not flowing properly through the system, so it has safely shut down to prevent overheating.
Your boiler is safely shutting itself down because the flame keeps going out shortly after it tries to start up.
Your boiler has detected an internal safety lockout related to its operating temperature and will need a Gas Safe registered engineer to investigate further.
Your boiler has failed to ignite or lost its flame, meaning it has temporarily stopped working to keep you safe.
Your boiler is displaying a general flashing error signal, meaning it has safely locked out and stopped working to prevent further issues.
Your boiler is displaying a general flashing error signal to indicate it has stopped working due to an internal safety lock-out.
Your boiler has detected an internal safety or communication fault with the fan and requires an inspection by a qualified professional.
Your boiler has detected an internal communication or sensor issue and has safely shut down to prevent potential damage.
Your boiler has lost safe communication with its internal computer board, so it has safely shut down to prevent damage.
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BoilerFaultCodes