Saunier Duval Themaclassic F23E Fault codes & diagnostics

Your boiler has detected that the water pressure level inside the heating system has dropped below the required amount to operate safely.

Your boiler has detected a general issue and has entered a safety lockout mode.

Your boiler is failing to light the flame properly, so it has turned itself off for safety until it is repaired.

Your boiler is struggling to clear exhaust gases safely, so it has turned itself off to prevent any risk.

Your boiler is failing to vent exhaust gases safely, so it has stopped working to prevent a hazard.

Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.

Your boiler has stopped working because it is unable to accurately measure the temperature of the water circulating through your radiators.

Your boiler is struggling to accurately measure the water pressure inside the system, which is preventing it from firing up safely.

Your boiler's computer system has encountered an internal error and can no longer control the heating or hot water functions.

Your boiler has lost the ability to accurately measure the temperature of the hot water it is trying to produce, so it has shut down to prevent overheating.

Your boiler is struggling to bring gas into the system to create a flame, so it has safely shut itself down to prevent any issues.

Your boiler has lost the connection to the sensor that monitors the temperature of your heating water, so it has shut down to prevent overheating.

Your boiler has detected that the water temperature is significantly different between the start and end of its heating circuit, which suggests the water is not circulating properly.

Your boiler is attempting to start up, but it is unable to keep the flame alight once it ignites, so it safely shuts itself down.

Your boiler is attempting to start its flame but is unable to stay lit, causing it to shut down for safety reasons.