4 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 |
|---|---|---|
| 41-920-43 | Xeon 80 ff | 2001–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 is not detecting the correct electrical power supply, which is usually caused by a blown internal fuse or a power cut.
Your boiler has automatically shut down because it has detected dangerously high internal temperatures.
Your boiler is failing to detect the correct airflow needed to safely burn gas and clear exhaust gases.
Your boiler has failed to light or stay safely lit, so it has locked out to prevent any unburnt gas from building up.
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BoilerFaultCodes