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 temporarily paused because the water inside has become slightly hotter than it is supposed to be.
Your boiler has temporarily stopped working because a safety switch outside the boiler, such as a room thermostat, timer, or external valve, has been triggered or disconnected.
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 has temporarily shut down because the water inside it has become dangerously hot, exceeding safe temperature limits.
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 has tried to light itself several times but has failed, likely because there is no gas supply or the ignition part is dirty or broken.
Your boiler is failing to light the flame or keep it running, which means it cannot provide you with heating or hot water.
Your boiler is detecting a flame inside the unit even when it has been instructed to switch off, which indicates a serious internal safety issue.
Your boiler has temporarily stopped working as a safety precaution and needs you to press a reset button to try and restart it.
Your boiler is failing to start up properly, meaning it cannot ignite to provide you with heating or hot water safely.
Your boiler has detected that the internal fan responsible for venting exhaust gases safely is either not spinning or communicating properly, so it has shut down to keep your home safe.
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 that the internal casing is getting too hot, indicating it is struggling to ventilate correctly or is running too hot internally.
Your boiler has detected a safety-related electrical overload or thermal issue inside the main burning chamber and has shut down to prevent damage.
Your boiler has detected that some of its internal settings have drifted outside of their safe operating limits, and it has stopped working as a precaution.
Your boiler has detected an internal software or settings error, which is preventing the system from starting up safely.
Your boiler has lost its programmed settings and needs to be reconfigured by a professional to operate correctly.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes