12 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is safely shutting itself down because the flame keeps going out while trying to run.
Your boiler is working normally and is simply adjusting its internal power levels to keep your water at the temperature you requested.
Your boiler has lost the ability to accurately measure the temperature of the central heating water, so it has shut down to prevent overheating.
Your boiler has detected an issue with its internal airflow or exhaust system, causing it to shut down for safety reasons.
Your boiler has lost its connection to the hot water temperature sensor, meaning it cannot monitor or heat the water in your cylinder safely.
Your boiler has detected that it is overheating and has automatically switched itself off to prevent damage.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler is struggling to pump water around your heating system correctly, which is preventing it from heating your home or water safely.
Your boiler has detected that the temperature of the exhaust gases leaving the flue is too high, causing it to shut down to prevent overheating.
Your boiler has stopped working because it cannot light its internal flame, which is likely due to an issue with the gas supply or the ignition process.
Your boiler has detected an issue with the internal ventilation system that prevents it from starting up safely.
Your boiler is struggling to get water moving through the system properly before it attempts to fire up.
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BoilerFaultCodes