13 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Logic Combi
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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 |
|---|---|---|
| 47-348-15 | isar m30100 | 2001–2004 |
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Your boiler has detected that the internal air extraction system is not working correctly, which prevents it from igniting safely.
Your boiler has detected an internal electrical fault near the part responsible for sensing the flame, preventing it from safely starting up.
Your boiler has detected a communication issue with the sensor that monitors the temperature of the exhaust gases, causing it to shut down for safety reasons.
Your boiler has detected that the electrical supply wires have been connected the wrong way round, preventing it from starting up safely.
Your boiler's internal computer is receiving confusing information from a temperature sensor, causing it to shut down to prevent overheating.
Your boiler is receiving an confusing signal from the pipe that brings water back from your radiators, so it has paused operation to prevent any potential strain on the system.
Your boiler is struggling to accurately measure the temperature of your hot water, which may lead to the water being too cold or failing to heat up at all.
Your boiler is failing to detect the burner flame, which means it will prevent itself from operating to keep you safe.
Your boiler has detected that the electricity supply wires are connected in the wrong order or that the electrical supply is unstable.
Your boiler's main control unit has identified an internal electronic error and has shut down for safety to prevent unpredictable system behaviour.
Your boiler's main computer control panel has detected an internal error, which means the system has safely shut down to prevent damage.
Your boiler is failing to light the flame or keep it running, which means it has safely shut itself down to prevent gas from building up.
Your boiler is failing to ignite the internal flame, which means it cannot produce any hot water or heating.
BoilerFaultCodes