14 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Main Eco System
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Your boiler has stopped working because it cannot light the flame, which is sometimes caused by a blockage in the waste-water pipe.
Your boiler has detected that it is running too hot and has automatically shut down to prevent damage or dangerous overheating.
Your boiler is struggling to push water around the system, likely because the water pressure has dropped too low or the pump is stuck.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water inside the system.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water inside the system.
Your boiler has stopped heating your home or water because it is failing to receive a proper temperature signal from its internal sensor.
Your boiler's computer system does not recognise the specific electronic board installed, preventing the unit from operating correctly.
Your boiler has lost its ability to accurately measure the temperature of the water used for your taps, causing it to shut down for safety reasons.
Your boiler has detected that it is getting too hot and has automatically shut itself down to prevent damage.
Your boiler has stopped working because the water pressure inside the system has dropped too low.
Your boiler is struggling to move water around your heating system, which is keeping it from heating your home properly.
Your boiler has lost power while it was already trying to report a different error, meaning the system is currently confused and needs a manual reset to restart correctly.
Your boiler has stopped working because it cannot detect a flame or is not receiving a steady supply of gas.
Your boiler has detected that the internal fan responsible for safely venting fumes is not spinning or communicating correctly, so it has shut down to prevent unsafe operation.
BoilerFaultCodes