21 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: ecoTEC plus
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Your boiler's temperature sensor is failing to provide a reading, which has caused the system to shut down for safety.
Your boiler is struggling to accurately measure the temperature of the water returning to it, which prevents it from heating your home safely and has caused it to shut down for protection.
Your boiler has detected a faulty temperature sensor reading, causing it to shut down to prevent overheating.
Your boiler's internal sensor that monitors the temperature of water returning to the system is reading incorrectly, causing the boiler to shut down for safety.
Your boiler is struggling to accurately read the temperature of your hot water cylinder because there is a faulty electrical connection or sensor.
Your boiler has switched itself off because it has become dangerously overheated and triggered a safety shut-down.
Your boiler has detected that the water pressure inside the system has dropped too low to operate safely.
Your boiler has detected that water is not circulating properly through the system, causing the water to get much hotter in one part of the pipe than another.
Your boiler is struggling because it does not have enough water circulating inside it, causing the system to heat up much faster than it safely can.
Your boiler has detected a potential overheating issue and has safely shut itself down to prevent damage.
Your boiler has detected a flame when it is not supposed to be lit, which is a safety lock-out to prevent potential issues.
Your boiler is failing to light because it cannot detect a flame, meaning you currently have no heating or hot water.
Your boiler has stopped because the flame inside has gone out and will not stay lit, meaning you currently have no heating or hot water.
Your boiler's fan is failing to spin at the correct speed, which prevents it from safely venting exhaust gases and starting your heating.
Your boiler's internal computer has encountered a serious internal error and can no longer control the heating system safely.
Your boiler's internal computer has encountered a critical communication error and cannot safely operate the system.
Your boiler has detected an internal computer error and has shut itself down as a safety precaution.
Your boiler has detected a failure in its internal computer memory, preventing it from operating correctly.
Your boiler's internal computer has encountered a serious internal error and cannot communicate properly with its own parts, meaning the boiler has shut down for safety.
Your boiler has detected an internal issue with its main brain, causing it to stop working to ensure your safety.
Your boiler’s internal computer is having a major communication error and can no longer safely operate the heating system.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes