11 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Logic System
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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 |
|---|---|---|
| 41-391-52 | icos system m3080 | 2001–2004 |
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 failing to detect the burner flame properly, so it has safely shut down to prevent any unburnt gas from building up.
Your boiler has successfully lit but the flame has gone out unexpectedly, meaning it cannot stay on to heat your home or water.
Your boiler has detected an issue with the water flow or temperature readings and has safely shut down to prevent damage.
Your boiler has detected that the water temperature inside the system has risen too high, causing it to shut down for safety.
Your boiler has detected a communication conflict between its internal electronic control panels, meaning it cannot currently coordinate its functions safely.
Your boiler has detected an issue with the internal computer software or a internal configuration error that prevents it from operating normally.
Your boiler has detected an internal communication error between its main control components and is unable to operate safely.
Your boiler has detected an issue with the heat exchanger or its temperature control, and it has stopped working to prevent potential damage.
Your boiler has detected a critical internal error that prevents it from starting, and it requires a professional safety check.
Your boiler has detected a communication error between its internal electronic brains, causing it to stop functioning for safety reasons.
Your boiler is struggling to keep its flame lit or cannot detect the flame, so it has safely shut itself down to prevent gas from building up.
BoilerFaultCodes