35 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has stopped working because it cannot accurately measure the temperature of the water leaving the unit to heat your home.
Your boiler has detected an electrical fault with the internal sensor that monitors the temperature of the water leaving the unit, causing it to shut down for safety.
Your boiler has detected an electrical fault with the internal sensor that monitors the temperature of the water used for your heating, causing the system to shut down for safety.
Your boiler has lost its ability to monitor the temperature of your hot water cylinder because a sensor has developed an electrical fault.
Your boiler has detected a technical fault with the sensor that monitors the temperature of your hot water tank, meaning it cannot heat your water accurately.
Your boiler has switched itself off because it has become too hot internally and needs to cool down for safety.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has shut down because the water is heating up too quickly or unevenly, suggesting a circulation problem.
Your boiler has shut down because the water inside is heating up much faster than it can be moved around the system, usually due to a blockage or a pump issue.
Your boiler has shut down because it detected that the exhaust gases are getting too hot, which is a safety feature to prevent internal damage.
Your boiler has shut down because it thinks it detected a flame when there shouldn't be one, or the flame signal is being misread.
Your boiler has tried to light the gas but failed, meaning it cannot provide heating or hot water until reset.
Your boiler was lit but the flame has gone out unexpectedly, which has caused the system to stop working for safety.
Your boiler is struggling to manage its internal temperature because the fan is spinning at the wrong speed, likely due to extreme cold or a mechanical issue.
Your boiler has sensed it is too cold and the fan is stuck trying to protect the internal pipes from freezing.
Your boiler has detected a communication error with the gas valve, preventing it from safely lighting the burner for heating and hot water.
Your boiler's internal computer is having trouble processing electrical signals from its various sensors.
Your boiler's electronic control board is receiving a confusing signal regarding the flame, which has caused the system to shut down for safety.
Your boiler’s control computer has lost its identity settings, meaning it no longer knows which specific model it is and has shut down as a safety precaution.
Your boiler has detected that the sensors measuring water temperature are not reading correctly or are out of sync, causing the system to shut down for safety.
Your boiler has detected that its flow and return sensors are providing conflicting readings, which prevents it from heating your home safely.
Your boiler has lost signal from its internal water pressure monitor, meaning it cannot confirm if there is enough water to run safely.
Your boiler's internal sensor that monitors water pressure has experienced an electrical failure and can no longer tell if there is enough surface water for the system to run safely.
Your boiler has failed to detect a rise in pressure when the pump started, meaning it cannot safely circulate water to heat your home.
Your boiler has detected a blockage in the drainage pipe or an issue with the flue, preventing exhaust gases or water from leaving the system safely.
Your boiler has detected a fault with a safety sensor designed to prevent the main heating unit from overheating, causing the system to shut down.
Your boiler has detected a safety issue with the part that controls the gas supply, causing it to shut down to prevent a fault.
Your boiler's computer memory has developed a technical error, meaning the internal control system cannot process instructions correctly.
Your boiler is confused because its temperature sensors are giving conflicting readings or are installed incorrectly, causing the system to shut down for safety.
Your boiler has shut down because its internal electrical components have become too hot and need to cool down.
Your boiler is having trouble creating the spark needed to light the gas or recognizing that a flame has started.
Your boiler is struggling to keep a steady flame lit, causing it to shut down for safety.
Your boiler's internal pump is not moving water around the system correctly, which has caused the boiler to stop working to prevent overheating.
Your boiler has lost its ability to monitor the temperature of your hot water cylinder because a sensor has developed an electrical fault.
Your boiler's internal communication system has lost power, meaning the different components cannot talk to each other to start the heating process.
BoilerFaultCodes