17 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: ecoTEC plus
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Your boiler is trying to start up but cannot successfully light the flame, so it has stopped working for your safety.
Your boiler is trying to start up but is failing to stay lit, so it has turned itself off for safety.
Your boiler has detected that it is getting too hot and has automatically shut itself down to prevent any damage or danger.
Your boiler has lost the ability to accurately measure the temperature of the water circulating through your heating system, so it has safely shut down to prevent overheating.
Your boiler is unable to read the temperature of the water returning from your radiators, so it has shut down to prevent overheating.
Your boiler's computer has lost the ability to communicate with its internal control sensors, so it has shut down as a precaution.
Your boiler's electronic control panel has lost communication with the main computer inside the unit, meaning the boiler has stopped working because it cannot receive instructions.
Your boiler's central control computer is not responding correctly, which has caused it to shut down for safety.
Your boiler has detected that the internal water temperature is dangerously high and will continue to shut itself off to prevent overheating.
Your boiler has detected that a flame is still burning inside even after it should have turned off, which is a safety concern that requires an immediate professional check.
Your boiler is not receiving enough electricity from your home's power supply to run correctly.
Your boiler is struggling to communicate with its control display, which prevents it from functioning correctly.
Your boiler has lost the connection to the temperature sensor that monitors your heating system, meaning it cannot tell how hot the water is and has shut down as a safety precaution.
The internal computer systems of your boiler are having a communication mismatch, meaning the boiler has stopped working because it cannot properly coordinate its internal functions.
Your boiler has detected that the water returning to it from your radiators is dangerously hot, causing it to shut down to prevent damage.
Your boiler has detected that the water temperature is rising far too quickly, so it has shut down to prevent potential overheating.
Your boiler has detected that the water temperature is rising too quickly compared to how fast it is circulating, suggesting a blockage or a failure in the pump moving water through your system.
BoilerFaultCodes