24 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Independent Combi
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Your boiler has temporarily paused because an internal valve is stuck in the middle position during a service mode check.
Your boiler has stopped working because the water pressure inside the system is too low to operate safely.
Your boiler's internal computer is having trouble communicating with its configuration settings, meaning it cannot safely start up.
Your boiler is failing to stay lit, which means it has safely shut itself down because it cannot consistently produce or hold a flame.
Your boiler has detected that the internal fan is not spinning correctly, which prevents it from safely venting gases, so it has shut down to protect your home.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water inside it, causing it to shut down for safety.
Your boiler's temperature sensor is providing incorrect readings or has disconnected, so the system has shut down to prevent overheating.
Your boiler is struggling to read the temperature of the water returning to it, so it has turned itself off as a precaution to prevent overheating.
Your boiler is unable to read the temperature of the water returning to it, so it has safely shut down to prevent overheating.
Your boiler is struggling to detect the current outdoor temperature, which means it cannot automatically adjust your heating to match the weather outside.
Your boiler is struggling to operate because the electricity supply from your home is too weak or unstable.
Your boiler's main electronic brain has lost its memory settings or needs to be reprogrammed by a professional.
Your boiler has detected that the temperature sensors for the water going in and out are reporting incorrect or swapped readings, which has caused the system to shut down for safety.
Your boiler has lost its flame while trying to run, which means it cannot heat your water or your radiators.
Your boiler has detected a dangerous difference in temperature between its internal sensors and has automatically shut down to prevent overheating.
Your boiler has lost communication with its internal memory chip, meaning it cannot operate safely until the settings are restored or the component is replaced.
Your boiler has detected that it is getting too hot or cannot move water through the system, so it has safely shut itself down to prevent damage.
Your boiler has detected that the flame inside has gone out unexpectedly, so it has shut itself down to keep your home safe.
Your boiler's temperature-sensing component is malfunctioning, which prevents it from safely controlling the heat, so it has turned itself off to prevent overheating.
Your boiler has attempted to restart itself too many times in a short period due to an underlying fault, so it has now locked itself out for safety.
Your boiler has detected an issue with the sensor that monitors the temperature of the water returning to the unit, causing it to stop running for safety.
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 has temporarily locked itself out because it tried to restart five times in a short space of time without successfully firing up.
Your boiler has lost its flame while running, meaning it is not getting enough gas or the spark is failing to keep the burner lit.
BoilerFaultCodes