33 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has lost its identity because the smart chip that tells it how to operate has failed or is disconnected.
Your boiler's internal computer memory card is experiencing a communication error, preventing the system from starting.
Your boiler has stopped working because there isn't enough water pressure in the system to operate safely.
Your boiler has started to light but the flame has gone out unexpectedly, meaning it has shut down for safety.
Your boiler has failed to light or has lost its flame while running, meaning it cannot heat your home or water.
Your boiler has stopped working because the fan that removes waste gases is not running at the correct speed or has failed.
Your boiler's internal thermometer has stopped working correctly, so the system is unable to tell how hot the water is and has shut down as a precaution.
Your boiler has detected a problem with the sensor that monitors the temperature of the water returning to the unit, causing it to stop firing for safety.
Your boiler is struggling to work out how hard it needs to fire because it has lost communication with the sensor that monitors the temperature outside.
Your boiler has detected that the electrical supply coming into your home is at too low a voltage to operate safely.
Your boiler’s internal computer chip hasn't been programmed with the correct instructions to tell the unit how to operate.
Your boiler's internal computer has either lost its settings or suffered an electrical failure, meaning the system cannot communicate with itself to start up.
Your boiler has detected that the water pipes connected to the heating system have likely been swapped or installed the wrong way around.
Your boiler has detected that water is not moving through the system properly, which is preventing it from heating up safely.
Your boiler is confused because the pipes measuring the water temperature seem to be the wrong way around or a sensor has come loose.
Your boiler has detected that heat is moving through the pipes in the wrong direction or a temperature sensor has failed.
Your boiler has shut down because it is getting too hot too quickly, likely because water isn't circulating through the system properly.
Your boiler has tried to light several times but cannot establish a steady flame, causing it to shut down for safety.
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 tried to light several times but failed, so it has shut itself down for safety.
Your boiler has detected that a temperature sensor is faulty or not reading correctly, which prevents the system from heating up safely.
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 has detected an issue with the sensor that monitors the temperature of the water returning from your radiators, preventing it from heating correctly.
Your boiler has identified a flame that shouldn't be there, causing it to shut down for safety purposes to prevent a potential gas leak or electrical error.
Your boiler has experienced a temporary electronic glitch that needs a simple system restart to clear.
Your boiler is receiving too little electrical power to operate safely, which may be caused by an issue with your home's electricity supply or a failing internal pump.
Your boiler has detected that there is not enough water in the system to operate safely, which is usually caused by a small leak or air being bled from radiators.
Your boiler has switched itself off because it became too hot, often because water isn't moving through the system properly.
Your boiler is unable to move water around the system because the internal pump is stuck or clogged.
Your boiler has switched itself off because it got too hot and needs a manual reset to start working again.
Your boiler has been manually reset too many times in a short window and has temporarily locked itself out to prevent damage.
Your boiler has tried to fire up too many times in a short window and has locked itself out as a safety precaution.
Your boiler has stopped working because the water level inside the central heating system is too low.
BoilerFaultCodes