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 |
|---|---|---|
| 41-397-96 | HE 12 HE 12 | 2004–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 displaying a service notification or a specific lockout state that requires a professional to check the internal sequence and settings.
Your boiler has shut down because the exhaust gases have reached a temperature that is too high, which is a safety feature to prevent damage to the system.
Your boiler is displaying an 'H' and 'E' sequence to indicate its current operating status or a diagnostic mode, often triggered by a system reset or power-up.
Your boiler has sensed that the exhaust gases are getting too hot and has shut down as a safety precaution to prevent internal damage.
BoilerFaultCodes