15 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 |
|---|---|---|
| 47-349-15 | LOGIC + COMBI C24 | 2016–present |
| 47-349-16 | LOGIC + COMBI C30 | 2016–present |
| 47-349-17 | LOGIC + COMBI C35 | 2016–present |
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Your boiler is struggling because it has lost the signal from the temperature sensor located outside your home, so it is defaulting to a standard operation mode.
Your boiler's computer memory card is not reading correctly, which prevents the system from starting up safely.
Your boiler is providing hot water for your taps as normal, but it is currently refusing to heat your radiators.
Your boiler is struggling to switch between heating your home and heating your hot water, which is causing your hot water supply to stop working while the heating continues to run.
Your boiler has lost all power and is completely unresponsive, meaning it cannot provide any heating or hot water.
Your boiler's internal memory card has developed a communication fault, meaning the control system cannot verify the specific settings for your model.
Your boiler has detected a flame when it shouldn't be there, so it has safely shut itself down to prevent any risk.
Your boiler is unable to start or maintain the ventilation process necessary to run safely, so it has locked itself out to prevent any issues.
Your boiler has stopped during operation because it can no longer detect the flame needed to heat your water, preventing it from functioning safely.
Your boiler is struggling to accurately measure the temperature of the water flowing through the system and has stopped working to protect itself.
Your boiler has become too hot or water is not moving through the system properly, causing the unit to shut down for safety.
Your boiler thinks a flame is present when it should be off, which is a safety lockout preventing the unit from starting.
Your boiler is receiving an unstable or incorrect amount of electricity from your home's mains supply, which is preventing it from operating correctly.
Your boiler has stopped working because the amount of water inside your heating system has dropped below the required level.
Your boiler is struggling to accurately measure the temperature of the water returning to it, so it has stopped working for your safety.
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BoilerFaultCodes