12 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has safely shut down because a built-in safety sensor detected dangerously high internal temperatures.
Your boiler has detected fire inside before it has actually opened the gas valve to supply fuel, which is a significant safety precaution that requires professional investigation.
Your boiler's temperature sensor on the main water pipe has failed or is giving an incorrect reading, causing the boiler to shut down for safety.
Your boiler has lost connection to the weather sensor outside your home, meaning it can no longer automatically adjust your heating based on the outside temperature.
Your boiler is temporarily unable to measure the temperature of the water returning to it, so it has safely shut down to prevent any issues.
Your boiler's air circulation system has stopped working, meaning the unit cannot safely vent old air or bring in fresh air to burn fuel effectively.
Your boiler has temporarily stopped working because the water pressure inside the system has dropped too low.
Your boiler has stopped working because it cannot detect enough water flowing through the system to heat safely.
Your boiler has lost communication between its internal control boards, meaning it cannot operate safely and has shut down.
Your home's heating is not working, but your hot water tank is still getting hot.
Your boiler is still heating your home, but it has stopped producing hot water from your taps.
Your boiler's screen has gone completely dark and unresponsive, meaning it has lost power and cannot operate.
BoilerFaultCodes