18 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is struggling to accurately measure your hot water temperature, which usually means it will stop providing hot water until the part is replaced.
Your boiler's main internal computer is failing to 'talk' properly to its control board, meaning it has temporarily stopped working for safety reasons.
Your boiler has lost the connection to the sensor that measures the heat inside your hot water storage tank, so it cannot accurately tell when the water is hot.
Your boiler's computer memory chip is loose or missing, meaning the system doesn't know which model it is and has stopped working for safety.
Your boiler has detected an internal computer memory error and needs to be reset or inspected by a professional.
Your boiler has detected an internal communication or sensor error that requires professional attention to resolve safely.
Your boiler has stopped working because the fan that clears away waste gases has failed to start or is spinning too slowly.
Your boiler temporarily cannot detect the outdoor temperature sensor, which usually just means your heating will default to a standard indoor schedule rather than adjusting automatically to the weather outside.
Your boiler has temporarily locked out because an external safety device, such as a room thermostat or underfloor heating limiter, has triggered to prevent overheating.
Your boiler is struggling to accurately read the temperature of the water circulating through your heating system, which means it may not switch on your heating or hot water correctly.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water flowing through your heating system.
Your boiler has detected that it is getting dangerously hot and has shut itself down to prevent damage, or it is struggling to safely push exhaust gases outside.
Your boiler is failing to light the gas or isn't detecting that the flame has started, causing the system to shut down for safety.
Your boiler has encountered an internal electronic error that is preventing it from operating correctly.
Your boiler has encountered an internal computer error and needs a reset to try and clear the glitch.
Your boiler is detecting a flame inside even though it has been told to turn off, which may indicate a safety sensor issue that needs urgent attention.
Your boiler has detected that a flame is still burning inside when it should have already turned off, which is a safety concern that requires an expert to inspect.
Your boiler has temporarily paused because the reset button was accidentally pressed, which is a safety feature rather than an actual fault.
BoilerFaultCodes