15 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected that water is not circulating correctly through the system, so it has safely shut down to prevent internal damage.
Your boiler is having trouble controlling the size of its internal flame, which means it cannot safely heat your water or home.
Your boiler is struggling to clear exhaust gases out through the flue, so it has safely shut itself down to prevent fumes from building up.
Your boiler has detected that the water temperature has risen too high and has safely shut itself down to prevent overheating.
Your boiler is failing to register a signal from the wall-mounted thermostat that tells it when to turn the heating on.
Your boiler has detected an internal safety issue and has shut itself down to prevent any damage or danger, meaning you currently have no heating or hot water.
Your boiler has stopped because the water pressure inside your heating system has dropped too low to operate safely.
Your boiler has detected an issue with venting away waste gases safely and has automatically shut itself down to protect your home.
Your boiler is trying to start up but cannot successfully light the internal flame to provide heat or hot water.
Your boiler has automatically turned itself off because it has become dangerously hot.
Your boiler has switched itself off because the water level inside your heating system has dropped too low to operate safely.
Your boiler is failing to circulate water because the internal pump has seized or stopped working, meaning you will currently have no heating or hot water.
Your boiler has stopped working because it couldn't light the flame needed to heat your water or home.
Your boiler has automatically turned itself off because it has detected that the water inside is running much hotter than it should be.
Your boiler has temporarily stopped working because it is struggling to safely push waste gases out of your home.
BoilerFaultCodes