8 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your Daikin heating system has detected an internal temperature reading error during its routine startup check and has safely locked out to prevent incorrect operation.
Your boiler has detected that the water inside is getting too hot because trapped air is blocking the flow and the circulation pump is not running properly.
Your heating system has detected an internal wiring or connection fault, which stops it from working properly to keep you safe.
Your boiler is trying to start up, but it cannot detect a flame because gas is not getting through properly or the ignition isn't sparking.
Your boiler is having trouble lighting or staying lit because it cannot detect a steady flame, which is likely due to a blocked drainpipe, low gas supply, or an ignition issue.
Your boiler is failing to detect a proper flame, so it has safely shut itself down to prevent any gas from building up.
Your boiler has stopped working because the internal airflow fan is not spinning at the correct speed, which usually means it is blocked or struggling to connect properly.
Your boiler has lost its connection to the weather sensor outside, but your heating and hot water should still continue to work normally using default settings.
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BoilerFaultCodes