24 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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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 heating system has dropped too low.
Your boiler is trying to start but keeps failing to keep the flame lit, so it has shut down as a safety precaution.
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 an issue with the fan that safely clears exhaust gases, preventing it from starting up for your safety.
Your boiler has detected a problem with the sensor that monitors the temperature of the water leaving the unit, meaning it cannot safely regulate heat.
Your boiler's temperature sensor is providing incorrect readings or has disconnected, so the system has shut down to prevent overheating.
Your boiler has detected a sensor problem that means it cannot accurately measure the temperature of the water returning to the unit, causing it to shut down for safety.
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 having trouble reading the outdoor temperature, which it uses to help run your heating more efficiently.
Your boiler is not receiving enough electrical power from the grid to operate safely and has shut down as a precaution.
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 switched itself off because the internal water temperature has become too hot, usually caused by a lack of water flow through the system.
Your boiler has failed to light several times and has shut down for safety, meaning you currently have no heating or hot water.
Your boiler has sensed a problem with the internal thermometer that monitors the water temperature leaving the unit, causing it to shut down for safety.
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 detected a sensor problem that means it cannot accurately measure the temperature of the water returning to the unit, causing it to shut down 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 thinks a flame is burning even though it shouldn't be, causing the system to shut down for safety.
Your boiler has temporarily locked itself for safety after failing to light several times in a short period.
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.
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BoilerFaultCodes