Vaillant ecoTEC Plus 826 Fault codes & diagnostics

Your boiler has lost the signal from the sensor that monitors the water temperature, causing it to stop heating your home as a safety precaution.

Your boiler has lost its connection to a sensor that measures the water returning to the system, causing it to stop heating as a safety precaution.

Your boiler has stopped working because it is unable to accurately measure the temperature of the water inside the unit due to a faulty electrical sensor connection.

Your boiler is currently unable to read the temperature of the water coming back into the system, so it has turned itself off as a safety precaution.

Your boiler has detected an overheating issue and safely turned itself off to prevent damage to 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 it is heating is not flowing through your pipes fast enough, causing it to overheat in one specific area.

Your boiler has detected that the water inside is heating up far too quickly, so it has safely shut itself down to prevent damage.

Your boiler is failing to ignite because it cannot open the internal valve that allows gas to flow to the burner.

Your boiler has detected an issue where it thinks a flame is present even when it should be turned off, so it has purposefully shut down to keep your home safe.

Your boiler is failing to start because it cannot light the gas flame needed to produce heat.

Your boiler has stopped because the flame inside has gone out and it is unable to restart itself.

Your boiler is unable to clear fumes properly because the internal fan is not spinning, so it has safely shut down to prevent any issues.

Your boiler's computer is having trouble recognising its own internal settings plug, which prevents it from starting up correctly.

Your boiler is having trouble communicating with its external controls or sensors, which will prevent your heating and hot water from working properly.

Your boiler is struggling to accurately measure the air flowing into the burner unit which forces it to shut down to prevent unsafe operation.

Your boiler is having trouble managing the air and gas mixture it needs to burn fuel safely and efficiently.

Your boiler has detected a problem with the way it manages the gas and air mixture required for safe combustion, causing it to shut down to prevent unsafe operation.

Your boiler has detected an issue with the gas control system and has safely paused its operation to prevent further problems.

Your boiler's internal computer is experiencing a memory error, meaning it has lost its settings and cannot safely manage the heating process.

Your boiler's computer has detected an internal communication error or a faulty temperature sensor, causing it to shut down to prevent incorrect operation.

The main computer inside your boiler is overheating, causing the system to shut down to prevent damage to its internal electronics.

Your boiler has detected an issue with how the flame is being monitored, so it has shut down to keep your home safe.

Your boiler is struggling to keep the internal flame burning consistently, causing it to shut down for safety reasons.

Your boiler’s internal computer has lost its configuration settings, meaning it no longer recognises itself correctly.

Your boiler has stopped working because it is unable to accurately measure the temperature of the water being heated inside the system.

Your boiler is struggling to accurately measure the temperature of the water flowing through it, so it has stopped heating to prevent potential damage.

Your boiler is struggling to accurately detect the water pressure inside the system because the sensor is sending an incorrect or missing signal.

Your boiler's electronic sensor is receiving an incorrect reading, which is stopping it from safely operating and providing heating or hot water.

Your boiler is not detecting the necessary water movement to heat your home, which is likely caused by a blocked pump or a faulty pressure sensor.

Your boiler has detected an issue with an external accessory, such as the condensate drainage pump or the ventilation system, which is preventing it from running safely.

Your boiler is struggling to accurately detect water temperatures because a sensor responsible for monitoring the heat exchange process has developed a connection fault.

Your boiler is struggling to pump hot water into your storage tank, which means you may have no hot water or a significantly delayed supply.

Your boiler is struggling because it detects an unusual temperature difference between the water leaving and returning to the unit, suggesting an issue with heat circulation or sensor accuracy.

Your boiler has detected that two of its water temperature sensors appear to be mixed up, preventing it from safely monitoring the heating system.

Your boiler has lost the digital connection to its hot water storage tank, which means it cannot properly coordinate heating the water supply.

Your boiler is having trouble recognising its internal configuration, which prevents it from starting up correctly.

Your boiler has detected that the fuel/air mixture is not burning correctly, which triggered a built-in safety check to prevent inefficient or unsafe operation.

Your boiler is struggling to detect water moving through the system properly, which is preventing it from safely starting up.