41 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 |
|---|---|---|
| 47-044-82 | ecoTEC plus 835 VUW 306/5-5 (H-GB) R6 | 2017–present |
| 47-044-83 | ecoTEC plus 825 VUW 196/5-5 (H-GB) R6 | 2017–present |
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Your boiler has lost the signal from the sensor that monitors the temperature of the water flowing out to your radiators, causing it to stop heating to prevent damage.
Your boiler has lost the signal from a sensor that monitors the temperature of the water returning to the unit, causing it to stop working to protect itself.
Your boiler has detected an electrical fault with the internal sensor that monitors the temperature of the water leaving the unit, causing it to shut down for safety.
Your boiler has stopped working because a sensor that monitors the temperature of the water returning to the unit has developed an electrical fault.
Your boiler is having trouble reading the temperature of your hot water cylinder because a sensor connection is faulty or shorted.
Your boiler has shut down because it has detected it is getting too hot, usually caused by a lack of water flow or a blockage in the system.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has switched itself off because the water temperature inside it is rising much faster than the water temperature being sent to your radiators, usually due to a circulation blockage.
Your boiler has shut down because it is heating up much faster than it should, which usually means the water isn't moving through the system properly.
Your boiler has detected a loose or broken electrical connection inside its main combustion chamber, meaning it cannot safely turn on the burner.
Your boiler has sensed a flame inside when there shouldn't be one, so it has shut down as a safety precaution.
Your boiler has failed to ignite and has locked itself out for safety, meaning you currently have no heating or hot water.
Your boiler was working but has suddenly turned off because the flame has gone out and it cannot manage to relight itself.
Your boiler has stopped working because the internal fan that safely removes exhaust gases is either stuck or not communicating correctly with the system.
Your boiler has lost communication between its internal computer and parts like the thermostat due to an electrical connection issue.
Your boiler is struggling to talk to the gas valve, which means it cannot safely control the fuel needed to create heat.
Your boiler has detected that the gas flame is not turning off when it should, which is preventing the system from running safely.
Your boiler's computer memory has suffered a technical glitch, meaning it can no longer remember its own settings and cannot operate.
Your boiler has detected a communication problem between its internal sensors or a fault in its main control board, causing the system to shut down for safety.
Your boiler's internal control board is getting too hot, usually because it is located too close to a heat source or there is a fault with the electronics.
Your boiler's internal computer is receiving a confusing signal regarding the flame, preventing the system from starting for safety reasons.
Your boiler's computer and internal display screen are no longer communicating correctly because they haven't been configured to recognize each other.
Your boiler has detected that a temperature sensor has stuck on a single reading, meaning it cannot accurately tell how hot the water is to safely heat your home.
Your boiler has detected that the temperature readings between two sensors don't match up, which prevents it from heating your water safely.
Your boiler is unable to accurately measure the water pressure because the internal sensor is sending an incorrect or missing signal.
Your boiler has detected a problem with the sensor that monitors water pressure, meaning it cannot accurately tell if there is enough water in the system to run safely.
Your boiler is unable to tell if its pump is running correctly, which means it has stopped working for your safety.
Your boiler has shut down because a safety sensor has detected that the main heat exchanger is getting too hot.
Your boiler has detected an issue with the drainage system that removes leftover liquid from the exhaust pipe or a fault with the safety flap inside the flue.
Your boiler is struggling to communicate with an external control box used for managing your hot water or heating zones, preventing it from functioning correctly.
Your boiler is operating normally and has successfully lit the flame to heat your water or radiators.
Your boiler is simply letting you know that the 'warm start' feature is active, which keeps a small amount of water pre-heated so you get hot water at your taps more quickly.
Your boiler is struggling to start the fan when you turn on your hot water taps, meaning the system cannot safely clear exhaust gases to begin heating.
Your boiler has detected that hot water is being called for, but it believes the pump is running when it shouldn't be or there is a circulation issue preventing proper operation.
Your boiler is having trouble lighting the flame when you turn on your hot water taps.
Your boiler is struggling to keep the flame lit while trying to heat your tap water, which usually means the system is cutting out during use.
Your boiler is temporarily cooling itself down after finishing a cycle for hot water.
Your boiler has paused operation because it believes the internal temperature is so low that the pipes are at risk of freezing.
Your boiler has temporarily paused because a safety flap in the flue system is not providing the correct signal to allow the burner to start.
Your boiler is pausing temporarily because it is struggling to circulate water quickly enough to keep the system cool.
Your boiler has temporarily paused operation because it detected a sudden rise in temperature and is waiting for the system to cool down or balance itself.
Not faults — these are normal operating states. Tap to expand.
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BoilerFaultCodes