24 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler's temperature sensor is providing faulty readings, so the system has shut down to prevent overheating or operating incorrectly.
Your boiler has detected an issue with the sensor that monitors the temperature of the exhaust gases leaving the unit, causing it to shut down for safety reasons.
Your boiler is struggling to accurately read the temperature of the water returning to it, so it has stopped working to prevent potential damage.
Your boiler has temporarily stopped working because it cannot accurately read how hot the water is inside the system.
Your boiler is struggling to move water around your heating system effectively, so it has shut down to prevent damage.
Your boiler is struggling to move water through the system effectively, which is causing it to shut down to prevent overheating.
Your boiler has detected that it is getting too hot and has safely shut itself down to prevent damage.
Your boiler has detected that it is overheating and has automatically shut down to prevent damage because the internal pump is not moving water correctly.
Your boiler has detected that it is running much too hot and has automatically shut itself down to prevent damage or safety risks.
Your boiler has detected that it is getting too hot and has automatically shut itself down to prevent damage.
Your boiler has too much water in the system, which puts extra stress on the internal parts and may cause it to shut down for safety.
Your boiler has detected that there is not enough water in the system to operate safely, causing it to shut down temporarily.
Your boiler has detected that water isn't moving through the system properly, which is causing it to overheat and shut down for safety.
Your boiler is failing to move hot water around your radiators, likely because the internal pump is blocked, seized, or air is trapped in the system.
Your boiler started to heat up but the flame went out unexpectedly while it was running.
Your boiler has detected that the temperature in the exhaust flue is too high, causing it to shut down for safety reasons.
Your boiler has tried to ignite but failed to stay alight, which is often caused by a lack of gas supply or a blocked condensation pipe.
Your boiler is trying to start but cannot detect a flame, likely because the gas supply is blocked or the ignition system has failed.
Your boiler has attempted to light the gas flame multiple times but has failed, so it has safely shut down to prevent gas from escaping.
Your boiler's fan is not spinning at the correct speed, which prevents the system from safely clearing exhaust fumes and starting the ignition process.
Your boiler has detected that the internal fan responsible for safely venting exhaust gases is not working or communicating correctly, so it has shut down to prevent unsafe operation.
Your boiler has lost the ability to measure the temperature of your hot water, so it has safely shut down to prevent overheating.
Your boiler has detected a flame inside the unit when it shouldn't be there, so it has automatically shut down to keep your home safe.
Your boiler has stopped working because the water pressure inside the system has dropped too low.
BoilerFaultCodes