24 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Vitodens 100-W B1KC
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The GC number on your boiler's data badge identifies the exact appliance and production years, as recorded in the UK Product Characteristics Database.
| GC number | Appliance (register name) | Produced |
|---|---|---|
| 41-819-12 | Vitodens 100 W WB1B 26kW System Boiler | 2008–2012 |
| 41-819-13 | Vitodens 100 W WB1B 30kW System Boiler | 2008–2012 |
| 41-819-14 | Vitodens 100 W WB1B 35kW System Boiler | 2008–2012 |
| 47-819-18 | Vitodens 100 W WB1B 26kW Combi Boiler | 2008–2012 |
| 47-819-19 | Vitodens 100 W WB1B 30kW Combi Boiler | 2008–2012 |
| 47-819-20 | Vitodens 100 W WB1B 35kW Combi Boiler | 2008–2012 |
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Your boiler is struggling to detect that water is circulating through the system, which is preventing it from safely starting up to provide heating or hot water.
Your boiler is struggling because it has lost the signal from the sensor that monitors the air temperature outside your home.
Your boiler has lost the connection to the thermometer installed outside your home, so it cannot automatically adjust your heating based on the outdoor weather.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water inside the system due to a faulty electrical sensor connection.
Your boiler has stopped working because it can no longer accurately read the temperature of the water inside the system.
Your boiler is struggling to accurately read the temperature of your hot water tank, which means it may fail to heat your taps properly.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water inside the system due to a faulty electrical sensor connection.
Your boiler's heat sensor has developed a wiring or electrical fault, which means the system cannot accurately measure the temperature of the water and has shut down as a precaution.
Your boiler has lost the connection to the sensor that measures how hot your stored hot water is, meaning it cannot properly monitor or heat your water cylinder.
Your boiler has lost the signal from a temperature sensor, which prevents it from safely controlling your heating and hot water.
Your boiler is having a temporary communication breakdown with your external room thermostat or smart control system, which may prevent it from firing correctly.
Your boiler has detected an electrical fault with the sensor that monitors the safety of the exhaust gases leaving your home, so it has stopped working to keep you safe.
Your boiler has detected a disconnected or faulty sensor that monitors the temperature of the gases leaving your flue, causing it to shut down for safety reasons.
Your boiler has detected an internal electronic malfunction and has shut down for safety reasons to prevent further damage.
Your boiler has detected an internal control failure that is preventing it from starting up correctly.
Your boiler has switched itself off because the waste gases exiting the flue are dangerously hot, which usually indicates the internal heat exchanger is blocked or failing.
Your boiler has detected that it is running too hot and has automatically shut down to prevent damage or overheating.
Your boiler is detecting a flame inside before it has actually been told to start, so it has safely shut itself down to prevent a potential hazard.
Your boiler is failing to light the flame properly, meaning it cannot provide heating or hot water until the ignition process is resolved.
Your boiler has detected that the fuel supply is failing to shut off precisely when it should, which is a safety mechanism trigger.
Your boiler's air circulation system is failing to start up correctly, which is preventing the unit from safely igniting and providing heating or hot water.
Your boiler has detected that the internal fan is still spinning when it should be switched off, which prevents the system from starting up safely.
Your boiler has detected an internal communication failure between the electronic brain and the internal fan, which prevents the unit from starting safely.
Your boiler's electronic brain has encountered a internal error and has safely shut itself down to prevent any unsafe operation.
BoilerFaultCodes