25 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Heatline Capriz
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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 |
|---|---|---|
| 47-157-16 | Sargon 30 | 2008–2009 |
| 47-157-17 | Sargon 35 | 2008–2009 |
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Your boiler is struggling to detect if water is moving through the system, which is preventing it from heating up your radiators or taps.
Your boiler's electronic brain is experiencing a critical internal failure and is unable to safely control the system.
Your boiler is struggling to detect the flow of water because it is having trouble reading the internal pressure levels correctly.
Your boiler is struggling to detect the flow of water because its internal sensor is faulty, which is preventing it from heating your home or water reliably.
Your boiler is struggling to detect the temperature of your hot water supply, so it has safely stopped heating to prevent potential issues.
Your boiler is currently unable to read the water temperature correctly, so it has shut down to prevent overheating while it waits for a repair.
Your boiler's water circulation device is not moving water effectively, which prevents your heating and hot water from working.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
Your boiler has detected a critical internal hardware fault with its main electronic control unit, preventing it from operating safely.
Your boiler has lost the ability to accurately measure the temperature of the water flowing through the system, so it has shut down to prevent damage.
Your boiler is not detecting water flowing through its pipes, which means it will stop heating your water or home to prevent damage.
Your boiler is failing to detect that water is circulating through the system, so it has shut down to prevent the internal components from overheating.
Your boiler is struggling to accurately measure the water pressure inside the system, which is preventing it from firing up safely.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler has detected an issue with the water circulation, meaning it has shut down to prevent internal damage or overheating.
Your boiler is failing to start up properly after multiple attempts.
Your boiler is experiencing a communication error between its internal electronic control systems, which is preventing it from operating correctly.
Your boiler has automatically shut down for safety because it detected that the internal water temperature has become dangerously high.
Your boiler is struggling to accurately measure the temperature of your hot water supply, so it has stopped heating water to prevent overheating.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water inside the system.
Your boiler has failed to start because it cannot detect a flame or drain water properly, so it has safely shut itself down to prevent any issues.
Your boiler has detected a fault with a safety sensor that monitors the temperature of the gases leaving your flue, meaning the boiler has shut down to prevent overheating.
Your boiler has detected that the air circulation system is not operating at the correct speed, so it has safely shut itself down to prevent unsafe operation.
Your boiler has detected that the internal exhaust fan is spinning when it should be turned off, which is a safety fault that prevents the boiler from starting up.
BoilerFaultCodes