19 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has shut down because the water inside its internal loop has become hotter than the system is programmed to allow.
Your boiler has detected that it has become dangerously hot and has shut itself down to prevent damage or overheating.
Your boiler is trying to start, but it cannot detect a flame, so it has safely shut down to prevent gas from building up.
Your boiler is confused because it senses an internal signal that makes it think the flame is burning even when it is not, causing it to shut down for safety.
Your boiler has detected that it is still sensing a flame even though it has tried to shut off the gas supply, which could indicate a safety issue with internal components.
Your boiler is struggling to accurately measure the temperature of the water being heated for your taps and shower, so it has stopped heating it to prevent overheating.
Your boiler is currently unable to accurately read the water pressure inside the system because the sensor responsible for this signal has stopped working or has lost its connection.
Your boiler is struggling to detect the flame correctly and will stop working to keep your home safe.
Your boiler has stopped because it cannot maintain a steady flame, meaning you currently have no heating or hot water.
Your boiler's computer is struggling to identify the specific configuration chip meant for your model, causing it to shut down for safety.
Your boiler is attempting to start but is failing to stay lit because it cannot detect a flame, which has caused it to shut down for safety.
Your boiler is attempting to light but is failing to detect a flame, meaning it cannot produce heat or hot water.
Your boiler has detected data from its internal temperature sensors that falls outside the expected range, prompting it to shut down for safety.
Your boiler is struggling to pump water around the system effectively, which is causing it to stop heating to prevent damage.
Your boiler has detected that the water inside the system has become dangerously hot and has shut itself down to prevent damage or overheating.
Your boiler has shut down because the water inside it is heating up much faster than it can be moved around your system.
Your boiler has detected that the water temperature is fluctuating unevenly inside the unit, forcing it to shut down to prevent damage.
Your boiler has detected that the water pressure in your heating system is dropping much faster than it should, which usually points to a leak somewhere in your radiators, pipes, or the boiler itself.
Your boiler has stopped working because the amount of water inside your heating system has dropped below the required level.
Not faults — these are normal operating states. Tap to expand.
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BoilerFaultCodes