45 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Promax Combi
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 detected an issue with the sensor that monitors the water temperature, causing the system to shut down as a safety precaution.
Your boiler is struggling to circulate water properly, which means it cannot produce hot water or heating until the internal pump is moving again.
Your boiler has detected a problem with the sensor that measures hot water temperature, which means your taps may not get warm.
Your boiler is failing to detect the flow of water needed to fire up the heating, meaning it cannot start the system.
Your boiler has stopped working because the water pressure inside the system has dropped too low.
Your boiler has detected a fault and stopped working, and it requires a manual reset to attempt to clear the error.
Your boiler has stopped working because it cannot safely vent waste gases or confirm that the fan is running correctly.
Your boiler is struggling to clear exhaust fumes safely, so it has purposefully turned itself off to prevent a hazard.
Your boiler has likely become too hot or water is not circulating correctly, causing it to shut down for safety.
Your boiler is failing to vent exhaust gases properly because it cannot confirm that the flue fan is working as it should, so it has shut down for safety.
Your boiler has tried to light but cannot detect a flame, which means it has locked itself out for safety.
Your boiler is trying to start but failing to stay lit, which means it cannot provide hot water or heating until the issue is resolved.
Your boiler has become too hot and has automatically shut down as a safety precaution.
Your boiler has detected an internal error and has temporarily stopped working to prevent damage, often caused by low system pressure or a temporary glitch.
Your boiler has detected an issue with how it clears exhaust gases, which has caused the system to shut down for safety.
Your boiler has detected an internal communication error or a disconnected jumper wire, which usually prevents the preheat function or the boiler from operating correctly.
Your boiler has tried to fire up but could not light the flame, causing it to shut down for safety.
Your boiler is likely struggling to provide hot water or maintain the correct temperature because its internal hot water thermometer has stopped working.
Your boiler has attempted to light but has failed to detect a flame, causing it to shut down for safety.
Your boiler has likely overheated, causing it to shut down automatically as a safety precaution.
Your boiler has stopped working because it cannot safely clear away exhaust fumes or the internal fan has failed to start.
Your boiler has switched itself off because the water pressure is too low or the pump that moves water around your radiators isn't working correctly.
Your boiler is struggling to correctly measure the temperature of your hot water, which usually means your taps will only provide lukewarm or cold water.
Your boiler has detected that the part responsible for measuring the temperature of your heating water is no longer working correctly, causing the system to stop as a safety precaution.
Your boiler is working normally and the burner is currently lit to provide heating or hot water.
Your boiler is failing to ignite because it is not receiving the signal to start the gas flow, meaning you will have no heating or hot water.
Your boiler is attempting to start but cannot detect a flame, so it has safely shut down to prevent gas from escaping.
Your boiler has detected that the internal mechanism responsible for safely venting exhaust gases is not operating correctly, so it has shut down to prevent any unsafe buildup of fumes.
Your boiler has stopped working because it cannot light its internal flame or keep it burning.
Your boiler has stopped working because the amount of water inside the system has dropped too low, which is a common issue that often just needs a quick top-up.
Your boiler has stopped working because it cannot light its internal flame or because the pipe that drains away waste water is blocked.
Your boiler has automatically shut down because it has detected dangerously high temperatures, effectively acting as a safety cut-out to prevent damage.
Your boiler is failing to clear combustion gases properly, which means the safety system has turned the unit off to prevent a build-up of fumes.
Your boiler is struggling to circulate water, either because there isn't enough water inside the system or the internal pump has stopped working.
Your boiler is struggling to detect the temperature of the water being heated, which means it will likely stop providing hot water until the faulty sensor is replaced.
Your boiler has stopped producing heat because it can no longer accurately read the temperature of the water circulating through your radiators.
Your boiler has encountered a temporary problem and requires a manual reset to restart its normal operation.
Your boiler has no power and the control panel lights are completely switched off.
Your boiler is receiving electrical power and is ready for normal operation.
Your boiler has stopped working because the water pressure in the system has dropped too low to operate safely.
Your boiler has too much water inside it, which is causing the safety valve to leak or trigger to protect the system from bursting.
Your boiler has stopped working because it failed to ignite, which could be due to a simple issue like a lack of gas or a more complex internal fault.
Your boiler has stopped working because it failed to light the flame or keep it burning.
Your boiler has switched itself off because it got too hot, which is a built-in safety feature to prevent damage or dangerous overheating.
Your boiler has sensed a temperature issue and has likely locked out to prevent overheating.
BoilerFaultCodes