36 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected an issue with the sensor that monitors shared heating systems or multi-boiler setups, causing it to temporarily stop working safely.
One of the internal modules within your boiler has detected a fault, while the rest of the system continues to try to operate.
Your boiler has stopped working because the water pressure inside the system has dropped too low.
Your boiler has stopped working because it cannot properly read the temperature of the water inside the system due to a faulty sensor connection.
Your boiler has failed to detect a flame after trying to light, so it has safely shut down to stop unburnt gas from flowing.
Your boiler has temporarily stopped working because it has detected an issue with its internal safety temperature cutoff switch.
Your boiler has detected a flame inside when it should be turned off, so it has safely shut itself down.
Your boiler has temporarily stopped working because it cannot detect water flowing through its internal system.
Your boiler has temporarily stopped working because a safety sensor has detected a potential overheating issue inside the system.
Your boiler has stopped working because it has detected a fault with the sensor that measures the temperature of the exhaust fumes.
Your boiler has detected an issue with the internal fan that controls airflow and combustion safely.
Your boiler has temporarily stopped working because it has lost the temperature reading from the heating pipe for one of your zones.
Your boiler has detected that a safety thermostat on your underfloor heating or mixed temperature zone has tripped, causing the system to shut off that zone for protection.
Your boiler has detected a faulty temperature sensor on your secondary heating zone, which means it cannot properly regulate the temperature for that part of your home.
Your boiler is having trouble communicating with the temperature sensor connected to your solar water heating system.
Your boiler is having trouble communicating with the temperature sensor in your hot water storage tank, which means it cannot correctly monitor or heat your stored water.
Your boiler has detected a fault with the temperature sensor connected to its solar panel system, meaning it cannot properly read the solar heat levels.
Your boiler has detected an issue with how it communicates with an attached solar heating system.
The boiler's control system is struggling to communicate with a specific accessory or secondary unit linked to your heating setup.
Your boiler's main computer brain is experiencing an internal electronic fault and cannot communicate properly with the rest of the system.
Your boiler has stopped working because it is unable to accurately detect the temperature of the water returning to it from your radiators.
Your boiler is struggling to communicate with a sensor that monitors the water temperature, meaning it has safely shut down to prevent overheating.
Your boiler is confused because its internal computer settings do not match the number of heating zones installed in your home.
Your boiler has lost its internal connection, meaning the main computer cannot talk to the control board properly.
Your boiler is having trouble communicating with an external control system or a secondary linked boiler, causing it to pause operations for safety.
Your boiler's internal components are currently unable to communicate with each other, which has caused the system to stop functioning as a safety precaution.
Your boiler is struggling to circulate water properly, causing the water leaving the boiler to be much hotter than the water returning to it.
Your boiler's external temperature sensor is sending an incorrect electrical signal, likely due to a loose wire or a faulty sensor unit, preventing the system from regulating the temperature correctly.
Your boiler is simply letting you know that it is currently warming up its internal water supply to ensure hot water is ready for you as soon as you turn on the tap.
Your boiler has detected an issue with the water flow or pressure sensor, causing it to shut down to prevent potential damage to the internal components.
Your boiler is failing to detect that the water is circulating properly, which prevents it from safely heating up.
Your boiler has detected an issue with the air supply or exhaust system, preventing it from operating safely.
Your boiler has detected an issue with the air supply or exhaust system, preventing it from safely removing combustion gases.
Your boiler has detected a problem with its internal water circulation system, meaning it cannot effectively move heat to your radiators or taps.
Your boiler's internal water pressure is too low, meaning there is not enough water circulating to heat your home or provide hot water.
Your boiler has detected that the water pressure inside the system has dropped too low for it to operate safely.
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BoilerFaultCodes