6 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is currently checking that there is enough airflow for it to start up safely; this light should turn off automatically once the system is ready to fire.
Your boiler is struggling to clear air through its internal system effectively enough to safely ignite the burner.
Your boiler is signalling that it is asking the internal air extraction motor to speed up to prepare for ignition.
Your boiler is correctly telling you that it has received a signal from your thermostat and is currently turning on the pump to circulate hot water to your radiators.
Your boiler is correctly indicating that it has received a request to start the pump for your hot water.
Your boiler is currently going through its normal startup process to ignite the burner and get your heating or hot water working.
BoilerFaultCodes