22 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 |
|---|---|---|
| 41-149-01 | System 30 | 2008–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 has shut down because it has reached a dangerously high temperature to prevent damage to the internal components.
Your boiler is trying to start up but cannot light the gas flame needed to provide heat and hot water.
Your boiler has started to heat up but the flame has unexpectedly gone out, causing the system to shut down for safety.
Your boiler has shut down to protect itself because the water inside has become far too hot.
Your boiler has shut down because the exhaust fumes have reached an unsafe temperature, triggered to prevent damage to the internal components.
Your boiler thinks it sees a flame even though it hasn't turned the gas on yet, which is a safety conflict that stops it from starting.
Your boiler has stopped providing heating and hot water because a internal heat sensor has failed, preventing the system from starting up.
Your boiler has shut down because a temperature sensor in the exhaust pipe has detected a fault or the system is unable to safely verify that a flame has been established.
Your boiler has stopped working because a sensor that monitors the temperature of the water returning from your radiators has developed a fault.
Your boiler is failing to light because gas isn't reaching the burner properly, meaning you will have no heating or hot water.
Your boiler has identified a communication problem with the internal fan, causing the system to shut down for safety while the fan runs continuously.
Your boiler has stopped working because it cannot detect a flame or has lost its electrical connection, meaning you currently have no heating or hot water.
Your boiler has stopped working because there is a serious electronic communication error within its internal control system.
Your boiler has failed to ignite because the electronic control board cannot properly read or communicate with the Burner Control Component (BCC).
Your boiler has detected an issue with the burner control component and failed to light, meaning you currently have no heating or hot water.
Your boiler has stopped working because it cannot detect a flame, likely due to a change or issue with the internal combustion control component.
Your boiler has stopped working because it cannot detect a flame or has encountered an issue with its internal combustion control system.
Your boiler has failed to ignite because the burner control system has not recognized or completed its installation correctly.
Your boiler has stopped working because the water pressure inside the system has dropped too low.
Your boiler has detected that there is not enough water flowing through the system or there is insufficient water pressure to operate safely.
Your boiler has failed to recognize its internal software chip or has failed to ignite, causing the system to shut down for safety.
Your boiler has no power and the screen is blank, meaning it cannot operate at all to provide heating or hot water.
BoilerFaultCodes