53 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: ecoTEC Plus 836
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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 |
|---|---|---|
| 47-044-61 | ecoTEC plus 938 H combi A VUI GB 386/5-5 A | 2015–2017 |
| 41-044-61 | ecoTEC plus 615 VU GB 156/5-5 | 2012–2015 |
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Your boiler's control panel and its internal computer are not talking to each other, meaning the unit cannot receive instructions to provide heat or hot water.
Your boiler has stopped working because it cannot communicate with the sensor that monitors the temperature of the water leaving the unit.
Your boiler has stopped working because it cannot accurately measure the temperature of the water returning to the unit.
Your boiler has lost the connection to the temperature sensor inside your hot water tank, meaning it cannot currently detect when the water needs heating.
Your boiler has lost communication with the built-in hot water storage tank sensor, which means it may struggle to provide consistent hot water.
Your boiler has detected an electrical fault with the internal sensor that monitors the water temperature leaving the unit, causing it to shut down for safety.
Your boiler has stopped working because it thinks the water returning to the unit is much hotter than it actually is, causing it to shut down for safety.
Your boiler has lost the ability to measure the temperature of your hot water cylinder because of a faulty sensor or a wiring issue, meaning it cannot heat your water correctly.
Your boiler has detected an electrical fault with the sensor that monitors your hot water tank, meaning it cannot accurately tell if your water is hot enough.
Your boiler has switched itself off because it has reached an unsafe temperature and needs to cool down.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has shut down because there is a significant difference between the water temperature leaving the boiler and the temperature returning to it, usually caused by a circulation problem.
Your boiler has shut down because the internal water temperature is heating up much faster than it can be circulated away, usually meaning the water is stuck or the pump is struggling.
Your boiler has shut itself down because the air being pushed out of the chimney pipe has become dangerously hot.
Your boiler is unable to open the internal valve that supplies gas to the burner, meaning it cannot ignite to provide heat or hot water.
Your boiler has detected a signal suggesting a flame is present even when it should be turned off, so it has shut itself down as a precaution to ensure your safety.
Your boiler is trying to light itself to provide heat, but it is failing to create a flame, likely because it is not getting enough gas or the spark isn't catching.
Your boiler was working but the flame went out and it cannot manage to light itself back up.
Your boiler's fan is unable to spin at the correct speed, which prevents the boiler from safely clearing exhaust fumes and starting the ignition process.
Your boiler is having trouble identifying its own internal settings due to a connection error between its electronic parts.
Your boiler has lost its ability to communicate with its external controls, such as your thermostat, due to an electrical glitch in the internal data wiring.
Your boiler is having trouble measuring the air flowing into it, so it has shut down to ensure it operates safely.
Your boiler is struggling to mix the correct amount of gas and air to burn properly, so it has safely shut itself down to prevent issues.
Your boiler is failing to ignite because it is not receiving enough gas to function properly.
Your boiler has detected an issue with the system that controls the gas and air mixture required to burn fuel safely, so it has shut down to prevent any risk.
Your boiler has temporarily stopped operating to protect itself from a potential hardware fault during its startup sequence.
Your boiler is unable to correctly control the flow of gas, causing it to shut down for safety purposes.
Your boiler has detected that the gas valve is not closing as quickly as it should, preventing the unit from shutting down the burner safely.
Your boiler's internal computer brain is having trouble reading its memory, causing the system to stop working for safety.
Your boiler has detected an internal communication error between its electrical sensors and the main control board, causing it to shut down for safety.
Your boiler's internal control board has become too hot and has shut down the system to prevent damage.
Your boiler's electronic control board has detected a confusing signal from the flame sensor, causing the system to shut down for safety.
Your boiler is struggling to keep its flame burning steadily, causing it to shut down for safety.
Your boiler’s control board has lost its identity settings, meaning the internal computer no longer knows which specific model it is supposed to be operating.
Your boiler is struggling to accurately measure the water temperature leaving the unit, usually because a sensor has failed or become disconnected.
Your boiler has detected that the sensors measuring water temperature going in and out are giving conflicting readings, so it has shut down as a safety precaution.
Your boiler is struggling to read how much water is in the system because of a sensor issue, which has caused it to stop working for your safety.
Your boiler's internal sensor has detected that the water pressure is too high or the sensor itself is sending an incorrect reading.
Your boiler is unable to sense water moving or pressure building when it tries to start up, which has caused it to shut down for safety.
Your boiler is struggling to push waste gases out through the flue or is unable to clear internal condensation water properly.
Your boiler is having trouble communicating with an external hot water control component, meaning it doesn't know the temperature of the water heading to your taps.
Your boiler is having trouble communicating with an internal sensor that helps regulate hot water temperature, which means your heating or hot water may stop working.
Your boiler's built-in hot water storage tank is failing to pump water correctly, which means you will likely have no hot water available.
Your boiler is firing up, but it doesn't detect the water getting hotter quickly enough, so it has shut down to prevent itself from overheating.
Your boiler is confused because its internal thermometers are giving conflicting readings and don't agree on how hot the water actually is.
Your boiler has stopped working because its internal thermometers are giving conflicting readings and believe they have been fitted to the wrong pipes.
Your boiler has lost the digital connection to its internal hot water storage tank, meaning it cannot properly coordinate heating the water for your taps.
Your boiler is having trouble communicating with the internal water storage tank, which means your hot water supply may be affected or inconsistent.
Your boiler's internal computer is receiving the wrong information about its own identity, preventing it from running safely.
Your boiler has detected that the fuel-to-air mixture is incorrect, which means it cannot burn gas safely or efficiently.
Your boiler has stopped working because the water pressure is too low for it to operate safely.
Your boiler's internal computer has forgotten its identity settings, preventing it from starting up correctly.
Your boiler is temporarily pausing its operation to allow internal parts to cool down or stabilize, which is a normal safety feature to prevent overheating.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes