9 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected that dangerous exhaust gases are not being cleared safely through the chimney, causing it to shut down to prevent carbon monoxide from entering your home.
Your boiler has stopped working because the water pressure is too low and needs to be topped up.
Your boiler has detected a fault with the temperature sensor that monitors the water leaving the unit, meaning it cannot safely regulate the heat and has stopped working.
Your boiler has failed to light the flame or cannot detect that the burner is on, meaning your heating and hot water will not work.
Your boiler has overheated, prompting a safety switch to shut the system down to prevent damage.
Your boiler is struggling to detect a flame, meaning it cannot stay on safely to provide heating and hot water.
Your boiler has lost communication with the component that controls the gas flow, meaning it cannot safely ignite to provide heating or hot water.
Your boiler has failed to ignite properly because it cannot detect that the water is warming up, so it has shut down as a safety precaution.
Your boiler has detected that its internal temperature sensors are giving conflicting readings, causing it to shut down for safety.
BoilerFaultCodes