78 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Atmotec
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Your boiler's internal computer is having trouble talking to its main control board, meaning the system cannot start up or operate.
Your boiler is having trouble communicating with the external pump that moves hot water around your radiators, meaning your heating likely won't work.
Your boiler is currently set to run at a lower power than needed, meaning your radiators might take a long time to heat up or may not get as hot as they should.
Your boiler has temporarily paused its burner to prevent it from switching on and off too frequently, which helps protect the internal components and improve efficiency.
Your boiler's internal pump is not circulating water correctly, which means your heating and hot water cannot function.
Your boiler is having trouble detecting the flame properly, which prevents it from firing up safely to provide heating and hot water.
Your boiler is taking a planned short break to prevent itself from turning on and off too frequently, which helps save energy and protect the internal parts.
Your boiler has lost connection with its internal temperature sensor, preventing it from heating your water safely.
Your boiler has stopped working because a sensor that monitors the temperature of the water leaving the unit has developed an electrical fault.
Your boiler has failed to light because it isn't receiving enough gas or cannot create a spark to ignite the burner.
Your boiler is failing to light the flame needed to heat your water or radiators.
Your boiler has sensed it is getting too hot and has shut down as a safety precaution to prevent damage.
Your boiler's internal temperature sensor has stopped sending information correctly, meaning the system doesn't know how hot the water is and has shut down as a precaution.
Your boiler's internal sensor has detected a broken connection, which means it cannot accurately measure the temperature needed to function properly.
Your boiler has detected a internal blockage that is stopping the water from circulating around your heating system correctly.
Your boiler has detected an internal blockage that is preventing water from circulating properly, which could lead to overheating.
Your boiler has detected an electrical short circuit with the hot water temperature sensor, meaning it cannot correctly monitor the water temperature.
Your boiler has detected an electrical issue where the incoming power wires may be connected in the wrong order or there is an unstable voltage supply.
Your boiler has become too hot and has shut itself down as a safety precaution to prevent damage.
Your boiler has detected that there is not enough water pressure in the system to operate safely, causing it to shut down to prevent overheating.
Your boiler has shut down because there is a significant temperature difference between the water going out and the water coming back, usually caused by a blockage or a pump failure.
Your boiler is struggling to move water through the system, which is causing it to stop running to prevent overheating.
Your boiler has shut down because the exhaust gases are getting too hot, which is a safety precaution to prevent damage.
Your boiler has stopped working because it cannot properly control the flow of gas needed to stay alight.
Your boiler has detected a flame when there shouldn't be one, which has caused it to shut down for safety purposes.
Your boiler is failing to light because it isn't getting enough gas or the spark that starts the flame is not working correctly.
Your boiler has lost its flame while running and cannot stay lit, meaning your heating and hot water have stopped.
Your boiler has stopped working because the fan that removes flue gases and brings in fresh air is not spinning at the correct speed.
Your boiler has lost communication with its smart controls or accessories, likely due to a wiring issue.
Your boiler has detected an internal electrical fault with the control system that manages the gas supply, causing it to shut down for safety.
Your boiler is unable to safely control the flow of gas required to light the flame, causing the system to shut down for safety.
Your boiler has detected that the gas valve is not closing properly or is leaking internally, which is a safety concern that prevents the unit from firing up.
Your boiler's internal computer brain has developed a memory fault and can no longer process instructions safely.
Your boiler's main control computer or internal sensors have detected an electrical communication error and have stopped the system to prevent damage.
Your boiler's internal control board has become too hot to operate safely and has shut down to protect itself.
Your boiler's internal computer is receiving a confused signal from the flame sensor, preventing it from safely starting the burner.
Your boiler is struggling to keep a steady flame lit because the gas supply is inconsistent or contains air bubbles.
Your boiler’s control board and display screen are no longer communicating correctly because the internal identity settings have been lost or mismatched.
Your boiler's internal thermometer is stuck on a single reading, meaning the system cannot tell how hot the water is and has shut down as a safety precaution.
Your boiler has sensed a conflicting temperature reading between its internal pipes, causing it to shut down for safety.
Your boiler's internal sensor can't accurately tell how much water is in the system, so the unit has shut down to avoid damage.
Your boiler has detected an electrical issue with its internal pressure sensor, meaning it cannot accurately tell how much water is in the system.
Your boiler has stopped working because it cannot detect the expected rise in water pressure when the internal pump starts up.
Your boiler has shut down because a safety sensor has detected that the internal heat exchanger is getting too hot.
Your boiler has detected a problem with the pump that removes wastewater or an issue with the flap that prevents gases from flowing back into the system.
Your boiler is having trouble communicating with the hot water temperature sensor because of a broken wire or a loose connection.
Your boiler has detected that no temperature change is occurring when the burner is lit, which usually means the water is not circulating correctly or the sensors are misreading.
Your boiler has noticed that its internal temperature sensors are giving conflicting or illogical readings, suggesting they are broken or incorrectly installed.
Your boiler has detected that its temperature sensors are not reading correctly, likely because they have come loose or were installed on the wrong pipes.
Your boiler is unable to start its fan, which is preventing the system from safely beginning the ignition process for heating or hot water.
Your boiler is struggling to circulate water because it has detected a problem with the flow from the pump.
Your boiler is currently preparing to provide heat and is circulating water through the system before the burner ignites.
Your boiler is struggling to light the burner to provide heating, which means your radiators will stay cold.
Your boiler is struggling to light the flame needed for heating.
Your boiler is currently firing up to provide central heating and is functioning as normal.
Your boiler's fan is running for longer than expected after a heating cycle, preventing the system from restarting properly.
Your boiler is struggling to clear leftover gases from the internal system after the heating cycle has finished.
Your boiler is staying in a cooling-down phase for longer than expected after the heating has finished.
Your boiler is staying in a cooling-down phase for too long after being used because it thinks water is still moving through the pipes when it shouldn't be.
Your boiler is temporarily pausing the heating because it has reached its target temperature and is waiting for a short period before restarting to prevent unnecessary wear.
Your boiler is currently taking a temporary planned break to prevent it from turning on and off too frequently, which helps protect the internal components.
Your boiler is failing to start even though you have turned on a hot tap because it cannot detect the air flow needed to run safely.
Your boiler has received a request to provide hot water, but it is taking longer than expected to start the heating process.
Your boiler is trying to provide hot water, but the internal fan is failing to start up properly to clear the exhaust gases.
Your boiler is having trouble circulating hot water because the pump isn't detecting enough water flow or has become stuck.
Your boiler is struggling to light properly when you turn on your hot water taps.
Your boiler is currently cooling itself down after providing hot water and will be temporarily unavailable for a few minutes.
Your boiler has detected that the temperature is too low and has paused itself to prevent the pipework from freezing.
Your boiler has paused its operation because a safety sensor has detected that an external component, such as an overflow pump or a temperature limit switch, has been triggered.
Your boiler has paused operation because a safety flap in the flue system is not opening or closing correctly, preventing waste gases from being safely cleared.
Your boiler is struggling to maintain a steady flame when running at its lowest power setting, which may cause it to stop working unexpectedly.
Your boiler has temporarily paused because it cannot sense enough water flowing through the system to operate safely.
Your boiler has temporarily paused its heating process because it has detected a sudden rise in temperature and needs time to cool down before restarting.
Your boiler is temporarily pausing operation because it has detected a potential issue with the burner flame not settling properly during its warm-up phase.
Your boiler is temporarily limiting its power because strong wind or a blockage is interfering with how the burner operates.
Your boiler has failed an internal test to confirm it is burning the correct type of gas, causing it to shut down for safety.
Your boiler has detected an issue with the sensor that monitors the temperature of the water coming back from your radiators, preventing it from heating correctly.
Your boiler is temporarily paused because it has detected a mismatch between the temperature sensors and needs to double-check them before starting up.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes