35 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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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 |
|---|---|---|
| 41-694-08 | ecoFIT pure 412 VU 126/6-3 OV (H-GB) | 2016–present |
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Your boiler's electronic brain is unable to talk to its internal controls, meaning it cannot operate safely.
Your boiler has stopped working because it has lost the connection to the sensor that measures the temperature of the water inside the system.
Your boiler has lost the signal from one of its internal temperature sensors, causing it to shut down for safety to prevent overheating.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water inside it, triggering a safety shut-off.
Your boiler has detected a faulty connection to a sensor that measures the temperature of the water returning to the system, causing it to stop运行 as a safety precaution.
Your boiler has lost the signal from the sensor that monitors your hot water tank’s temperature, so it may stop heating your water to prevent overheating.
Your boiler has stopped working because it does not have enough water inside the system to run safely.
Your boiler has detected that the water inside it is heating up or moving much differently than it should, so it has shut itself down to prevent overheating.
Your boiler has detected that the water inside it is heating up much faster than it should, so it has shut down to prevent damage.
Your boiler has detected that the exhaust gases leaving the system are dangerously hot and has shut itself down to prevent damage or safety risks.
Your boiler has detected a signal suggesting a flame is present when it should be switched off, causing it to shut down for safety reasons.
Your boiler is attempting to start but cannot successfully light the flame to heat your water.
Your boiler is struggling to stay lit because the flame it produces keeps going out while it is trying to run.
Your boiler has detected an issue with its internal air extraction system, meaning it has shut down to prevent unsafe operation.
Your boiler is having trouble communicating with its external controls, such as your thermostat or programmer, due to an electrical signal error.
Your boiler has detected an internal electrical issue that is preventing it from safely controlling the gas flow, so it has shut down to keep your home safe.
Your boiler has detected an issue with the internal gas valve's software or hardware, causing it to shut down for safety reasons.
Your boiler's computer has encountered an internal memory error, meaning it can no longer process instructions correctly and has safely shut down.
Your boiler has detected an internal issue with its electronic control system which is preventing it from operating safely.
Your boiler has detected an internal issue with the temperature monitoring system and has shut itself down to prevent overheating or damage.
Your boiler has detected an issue with its internal electronic monitoring system, causing it to shut down for safety reasons.
Your boiler is struggling to keep the internal flame burning consistently, causing it to shut down for safety reasons.
Your boiler's computer has lost its identity settings, meaning it no longer knows how to communicate correctly with its internal parts.
Your boiler is struggling to accurately measure how hot the water inside it is, so it has stopped working as a safety precaution to prevent overheating.
Your boiler has detected that the water temperature readings at the flow and return pipes do not match as expected, causing the system to stop working to protect itself.
Your boiler's water pressure sensor is sending an incorrect signal, which means the system cannot accurately detect the water level inside the boiler.
Your boiler's internal water pressure sensor is sending an invalid electrical signal, meaning the system cannot accurately read how much pressure is inside.
Your boiler is unable to confirm that water is moving around the system because it cannot detect a change in pressure when the internal pump starts.
Your boiler has detected that it is getting too hot inside and has shut itself down to prevent any damage to its internal parts.
Your boiler is struggling to clear away liquid waste or detected a blockage in the exhaust system, which has caused it to stop working as a safety precaution.
Your boiler is struggling to detect a normal change in water temperature, meaning it cannot accurately tell how hot the system is getting.
Your boiler has stopped working because it is unable to accurately read the temperature of the water inside the system.
Your boiler is failing to light the flame properly, which means it cannot produce any heat or hot water.
Your boiler is unable to safely control its gas supply, which prevents it from firing up to provide your heating and hot water.
Your boiler is not detecting that water is moving through the system properly, which means it has safely shut down to prevent overheating.
Not faults — these are normal operating states. Tap to expand.
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BoilerFaultCodes