15 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Vitodens 100-W
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Your boiler has stopped working because it is not receiving enough gas to light the flame safely.
Your boiler has stopped working because the electricity supply it is receiving is weaker than it needs to operate safely.
Your boiler has shut down because it has detected an overheating issue and has locked itself for safety.
Your boiler has failed to ignite and cannot provide heating or hot water, likely because it hasn't detected a flame after several attempts.
Your boiler has stopped working because the fan is unable to clear air from the combustion chamber properly.
Your boiler has automatically shut down for safety because it detected that it has become dangerously overheated.
Your boiler has detected a flame signal before it has even attempted to ignite, which means it has safely shut down to prevent a dangerous buildup of gas.
Your boiler has failed to light the gas flame required to provide heating and hot water.
Your boiler is struggling to clear exhaust gases or draw in fresh air because a sensor is detecting an airflow issue during startup.
Your boiler has stopped working because a sensor that measures water temperature is providing an incorrect signal, causing the system to shut down for safety.
Your boiler has stopped working because it has lost the connection to the sensor that monitors the internal water temperature.
Your boiler has stopped heating your domestic hot water because it is having trouble reading the temperature signal from the water cylinder sensor.
Your boiler has detected a faulty connection in the sensor that monitors the temperature of your hot water, which is preventing the system from heating water for your taps.
Your boiler has lost the connection to the temperature sensor that tells it when your hot water cylinder needs heating, so it has stopped heating your water to prevent potential overheating.
Your boiler has lost the signal from the sensor that monitors your hot water temperature, so it has stopped heating water to prevent the system from overheating.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes