20 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected an unusual temperature difference between the water leaving and returning to the unit, suggesting the water isn't flowing correctly.
Your boiler has detected that the water pressure in the system is too low to operate safely and has shut down as a precaution.
Your boiler has stopped working because the water pressure inside the system has dropped too low.
Your boiler has encountered a technical communication or internal sensor error and has stopped working as a safety precaution.
Your boiler has failed to light the flame or detect the flame after trying to start, which has triggered a safety shutdown.
Your boiler has detected a flame when there shouldn't be one, or the sensor incorrectly thinks a flame is present before the ignition process starts.
Your boiler has shut down because it has detected it is getting too hot, likely due to a circulation problem or a component failure.
Your boiler has detected an issue with the fan or its ability to clear exhaust gases, which has caused the system to stop working for safety reasons.
Your boiler has detected that the water pressure is too low for the system to operate safely.
Your boiler has detected that the water pressure is either too low or the sensor used to measure it is faulty, causing the system to stop working for safety.
Your boiler is struggling to monitor its water pressure correctly because an internal sensor is giving an incorrect signal or has failed.
Your boiler is receiving the wrong amount of electrical power from your mains supply, causing the system to shut down for safety.
Your boiler's hot water sensor has failed or is sending incorrect readings, meaning your taps and showers may stay cold.
Your boiler's electronic control board is struggling to regulate the gas flame correctly, which prevents the system from running at the right temperature.
Your boiler has detected a fault with the sensor that monitors and controls the water temperature in your main heating circuit.
Your boiler has detected that the water temperature returning to the unit is too high or is rising too quickly, causing it to shut down for safety.
Your boiler has detected an unsafe level of carbon monoxide or a combustion error and has shut down for your safety.
Your boiler has detected a blockage or issue with the flue pipe that prevents dangerous exhaust fumes from leaving your home safely.
Your boiler has shut down because the exhaust gases are getting too hot, which is a safety mechanism to prevent damage to the unit.
Your boiler has detected that the main part responsible for heating your water is becoming blocked or inefficient and needs a professional service.
BoilerFaultCodes