22 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Remeha Tzerra
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Your boiler has detected that the water inside the system has become hotter than it should be, causing the system to shut down for safety.
Your boiler has detected that the water returning to it is hotter than the water leaving it, which suggests a possible issue with the internal pump or a sensor reading error.
Your boiler has detected an electrical safety issue with its power connection and is shutting down to prevent damage or danger.
Your boiler is failing to light because it cannot detect a flame after several attempts, meaning you currently have no heating or hot water.
Your boiler is failing to light the flame or keep it running, so it has safely shut itself down to prevent a gas build-up.
Your boiler has detected a flame inside when it should be turned off, which is a significant safety concern that prevents the system from operating.
Your boiler has detected that the water level inside the system is too low or that the internal pump is unable to circulate water effectively.
Your boiler's air supply fan is not operating correctly, which prevents the unit from starting or heating your home safely.
Your boiler has detected that the internal compartment is getting too hot, so it has safely shut itself down to prevent overheating.
Your boiler has detected that some of its internal settings or operating data have fallen outside of their allowed range, causing it to stop working to prevent damage.
Your boiler's internal computer is struggling to read its own settings, meaning it cannot safely start up until the configuration is corrected.
Your boiler has lost its specific configuration settings, meaning it has reverted to a factory state and cannot operate your heating or hot water correctly.
Your boiler has temporarily paused heating because it has already reached the temperature you set, but it is currently waiting for a short safety delay before it starts up again.
Your boiler has temporarily stopped because it detected that the water inside is getting hotter than the temperature you have set, likely due to poor circulation.
Your boiler has detected that the water inside is heating up too quickly or is struggling to circulate, so it has safely shut itself down to prevent internal damage.
Your boiler has stopped working because one of its internal temperature sensors is providing faulty data, preventing the system from safely heating your home.
Your boiler is struggling to ignite or begin its normal operation sequence, so it has locked itself out for safety.
Your boiler is failing to start up properly, meaning it cannot provide heating or hot water at this moment.
Your boiler has detected an electrical safety fault, usually indicating that the appliance is not properly connected to the building's electrical grounding system.
Your boiler is failing to start up properly, meaning it cannot ignite to provide you with heating or hot water safely.
Your boiler is struggling to push water around the system, usually because the pressure is too low or air is trapped inside the pipes.
Your boiler has detected a safety-related electrical overload or thermal issue inside the main burning chamber and has shut down to prevent damage.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes