58 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Suprima
This boiler uses LED flash patterns
Count the flashes in one repeating group before the pause. That number is your fault code. Do not reset until you have noted it. How to read fault codes →
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Your boiler has stopped working because it failed to ignite or got too hot, and it now needs a manual reset to try and start again.
Your boiler has detected an internal issue and has safely shut itself down to prevent damage, meaning you currently have no heating or hot water until it is reset or repaired.
Your boiler has shut itself down for safety because it failed to light or detected an internal problem.
Your boiler has stopped working and entered a safety shutdown mode, meaning it will not provide heating or hot water until it is reset or repaired.
Your boiler has detected a internal problem and has safely switched itself off to prevent potential damage or unsafe operation.
Your boiler has detected that the electrical supply is incorrectly connected and is refusing to start as a safety precaution.
Your boiler has detected a faulty sensor that monitors the internal water levels, causing it to shut down to prevent potential overheating.
Your boiler has failed to light the gas after several attempts, which means your heating and hot water will not work until the system is reset.
Your boiler is failing to light the gas even though it is trying to start up.
Your boiler is failing to light the gas to create a flame, meaning you will not have any heating or hot water until it is reset or repaired.
Your boiler has completely lost power, meaning it cannot provide any heating or hot water, and the display screen is dark.
Your boiler has temporarily paused its operation because it has detected a minor inconsistency in its internal readings, such as water pressure or temperature.
Your boiler is operating normally and is actively heating your water or home.
Your boiler has detected that the water leaving the unit is getting too hot too quickly, causing it to shut down to prevent damage.
Your boiler is working correctly but has reached its maximum temperature for the moment and is pausing until it needs to fire up again.
Your boiler is briefly pausing itself to prevent the system from turning on and off too frequently, which helps protect the internal parts from unnecessary wear.
Your boiler is simply cooling itself down by pushing leftover heat into your radiators after the burner has finished its cycle.
Your boiler has detected a communication failure with a internal safety sensor, causing it to shut down to prevent unsafe operation.
Your boiler has detected that it is becoming dangerously hot inside its outer shell and has switched itself off to prevent damage or fire risk.
Your boiler's internal computer brain has developed a critical error and is now unable to control the heating or hot water system safely.
Your boiler has no electrical power, meaning the controls and display are completely dead.
Your boiler has detected that there is not enough water inside it to operate safely, so it has shut down to prevent internal damage.
Your boiler has detected a faulty internal safety sensor which forces the system to shut down to prevent damage.
Your boiler has tried to light several times but has been unable to produce a flame, meaning your heating and hot water will not work.
Your boiler has become too hot and has automatically shut itself down to prevent damage.
Your boiler has detected an issue with how exhaust gases are being cleared from the system, and it has shut down as a safety precaution.
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 fan, which safely removes exhaust fumes, is not spinning at the correct speed.
Your boiler has stopped working because it cannot correctly measure the temperature of the water inside the system.
Your boiler has detected an issue with a safety sensor that monitors the temperature of the unit’s casing, causing the system to stop working for safety.
Your boiler has detected an issue with the internal electrical connection that controls the gas supply, meaning it is currently unable to ignite safely.
Your boiler's main internal computer has developed a fault and can no longer communicate with the rest of the system.
Your boiler has stopped working because air is trapped in the pipes or the water isn't flowing correctly through the system.
Your boiler is struggling to accurately detect the temperature of the water returning to it, so it has stopped operating to prevent potential overheating.
Your boiler has switched itself off because it has detected air bubbles trapped in the system or a lack of water flow, which is causing it to overheat too quickly.
Your boiler has stopped working because the internal component responsible for clearing spent gases is not operating correctly.
Your boiler is struggling to pump water around your heating system effectively, which prevents it from warming your radiators or taps.
Your boiler's computer is experiencing an internal glitch and cannot talk to the rest of the system to safely operate your heating or hot water.
Your boiler has lost its connection to the digital control panel or thermostat, meaning it cannot receive instructions to fire up.
Your boiler's internal computer has flagged a critical error and has stopped working to prevent further damage.
Your boiler has detected that the water temperature is not circulating correctly between the heating pipes, causing it to shut down to prevent damage.
Your boiler is continuing to run its internal fan after the heating or hot water has switched off to safely clear out any leftover gases, which is a normal design feature.
Your boiler is currently running a process to clear any leftover gases from the burn chamber before it attempts to light, which is a normal safety routine.
Your boiler has stopped working because the internal fan, which safely clears exhaust gases, isn't spinning at the correct speed.
Your boiler is trying to start but the flame is cutting out immediately, which means it cannot safely keep the heating or hot water running.
The boiler is failing to register that water is moving through the pipes, so it has stopped heating to protect itself from overheating.
Your boiler is currently reporting that the gas supply is active and the burner is operating as normal.
Your boiler is failing to ignite the gas needed to create heat, meaning you currently have no heating or hot water.
Your boiler is currently running its usual safety checks before it attempts to light the burner.
Your boiler has stopped working for safety reasons because it detected an internal fault and has shut itself down to prevent damage.
Your boiler is briefly keeping the pump running to move leftover heat away from the unit, which is a normal part of the cooling-down process.
Your boiler is currently running its internal pump to move leftover hot water away from the heating components to prevent overheating, which is a normal part of the shutdown cycle.
Your boiler has lost its ability to measure the temperature of the water returning to it, so it has shut down to prevent potential damage.
Your boiler's temperature sensors are giving conflicting readings, which is causing the system to stop working reliably to prevent overheating.
Your boiler is struggling to accurately measure the temperature of the water flowing through it, so it has shut down as a precaution to prevent overheating.
Your boiler has detected an electrical fault with the sensor that detects the flame, causing it to shut down for safety reasons.
Your boiler is currently in idle mode and waiting for a signal from your thermostat or hot water timer to start working.
Your boiler has detected an electrical wiring error where the power wires appear to be connected incorrectly, which is a significant safety risk.
BoilerFaultCodes