11 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected that it has become too hot and has automatically switched itself off to prevent any damage.
Your boiler has tried to light the flame five times but failed, so it has safely shut itself down to prevent a build-up of unburnt gas.
Your boiler has had a new computer chip installed and is currently waiting for you to simply acknowledge the change so it can start working again.
Your boiler has lost connection to its 'brain' or memory chip, causing it to completely stop heating your home and water as a safety precaution.
Your boiler's computer has encountered a memory corruption error, meaning it has forgotten how to run the heating system properly.
Your boiler is struggling to detect that the internal fan is venting air properly, which prevents it from igniting safely.
Your boiler is struggling because the electricity supply feeding it is unstable or weaker than it needs to be to operate correctly.
Your boiler is failing to ignite or stay lit because it cannot detect a flame, meaning you currently have no heating or hot water.
Your boiler is struggling to regulate the temperature of your hot water, which may cause it to be too cold or scalding hot.
Your boiler has automatically shut down because it has detected that its internal water temperature has become dangerously high.
Your boiler's internal computer has encountered a critical error during its automatic safety checks and cannot safely operate, requiring a professional to investigate.
BoilerFaultCodes