17 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is detecting a flame inside the unit when it should be switched off, which is a safety mechanism to prevent it from firing up incorrectly.
Your boiler has detected an electrical fault in its internal wiring, which has caused it to shut down to prevent further damage.
Your boiler has failed to light the burner after several attempts, so it has shut down for safety reasons to prevent a gas build-up.
Your boiler's electronic brain has encountered an internal error and has safely shut down to prevent further issues.
Your boiler is struggling to clear air out of its system or is failing to pull in enough fresh air to burn correctly, causing it to shut down for safety.
Your boiler's internal computer has encountered a software or communication error and has safely shut itself down to prevent damage.
Your boiler has detected that the water inside the system is getting dangerously hot and has shut itself down to prevent damage.
Your boiler is detecting that the water returning from your radiators is hotter than it should be, suggesting a potential problem with your heating system's circulation or heat exchange.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water inside the system.
Your boiler has detected that the water inside the system is becoming dangerously hot and has shut itself down to prevent damage or overheating.
Your boiler has stopped because the internal fan is failing to start, which prevents the unit from safely venting exhaust gases.
Your boiler's ventilation fan is running continuously even when it isn't trying to heat your home.
Your boiler has detected that the water inside the system has become dangerously hot and has shut itself down to prevent damage or overheating.
Your boiler has lost the ability to accurately measure the water temperature, so it has safely shut itself down to prevent overheating.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water inside the system.
Your boiler has lost the ability to measure how hot the water inside it is, so it has safely shut down to prevent overheating.
Your boiler is struggling because it has lost the signal from a sensor that monitors the temperature of the water circulating back into the unit, causing it to shut down to prevent potential overheating.
BoilerFaultCodes