33 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Logic Heat
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Your boiler has lost its identity because the small memory chip inside has either moved or failed, meaning the system can't start up.
Your boiler has lost communication with its internal digital identity chip, meaning it cannot confirm its own model and safety settings to operate correctly.
Your boiler has detected that the water pressure in the system is too low to operate safely and effectively.
Your boiler has started to light but the flame has unexpectedly gone out, causing the system to shut down for safety.
Your boiler is failing to stay lit or cannot detect a flame, which means your heating and hot water have stopped working for safety reasons.
Your boiler has detected an issue with the fan that safely pushes waste gases out of the flue, causing the system to shut down for safety.
Your boiler has lost its ability to measure the temperature of the water leaving the unit, meaning it cannot operate safely and has shut itself down.
Your boiler's internal sensor that monitors the temperature of the water returning to the unit has developed a fault, preventing the system from operating correctly.
Your boiler has lost connection with its outdoor thermometer, meaning it cannot automatically adjust its temperature based on the weather outside.
Your boiler has detected that the electricity supply coming into your home is too low for it to operate safely.
Your boiler's internal computer brain hasn't been set up correctly to tell it which model it is, so it doesn't know how to operate.
Your boiler's internal computer has lost its settings or developed a technical fault, preventing the system from starting up.
Your boiler has detected that the pipes carrying water in and out of the unit have been installed or connected the wrong way around.
Your boiler is unable to move water around the system, which is preventing it from heating your home safely.
Your boiler has detected that the water temperature is rising in a way that suggests the heating pipes might be mixed up or a sensor is dislodged.
Your boiler has sensed that the internal water temperature readings are backwards, which usually means a sensor has come loose or is failing.
Your boiler has detected that the water is getting too hot too quickly, likely because it cannot flow through the system properly.
Your boiler has stopped trying to light after several failed attempts, which means it has safely shut itself down for your protection.
Your boiler has shut down because it has detected it is getting too hot or that water is not moving through the system properly.
Your boiler has failed to light because it cannot detect a flame, causing the system to lock itself for safety.
Your boiler has detected that water is not circulating correctly or a temperature sensor has stopped working, causing the system to shut down for safety.
Your boiler has been manually reset too many times in a short period and has temporarily locked itself out for safety.
Your boiler has detected a problem with the sensor that monitors the temperature of the water returning from your radiators.
Your boiler thinks it sees a flame even though the burner hasn't been turned on, causing it to shut down for safety.
Your boiler has experienced a temporary communication error or power fluctuation and simply needs to be restarted.
Your boiler is not receiving enough electrical power to operate correctly, which is likely caused by an external supply issue or a faulty internal component.
Your system does not have enough water in it to operate properly, causing the boiler to shut down as a safety precaution.
Your boiler has become too hot and has shut itself down as a safety precaution to prevent damage.
Your boiler's internal pump has stopped spinning, which means hot water cannot be moved around your radiators or taps.
Your boiler has shut down because a temperature safety limit was reached and it now needs to be manually cleared to restart.
Your boiler has been manually reset too many times in a short window and has temporarily locked itself out as a safety precaution.
Your boiler is repeatedly struggling to stay alight and has automatically shut down for safety after trying to start five times in a short period.
Your boiler has stopped working because the water pressure in the pipes has become too low for it to operate safely.
BoilerFaultCodes