33 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has automatically shut down because it detected that the internal water temperature became dangerously high.
Your boiler has stopped working because it cannot detect a flame or is not receiving gas to ignite.
Your boiler has automatically shut down because a safety sensor detected that exhaust gases are getting too hot near the flue collector.
Your boiler has automatically shut down because the internal water temperature has risen dangerously high.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler has lost connection to the outdoor temperature sensor, meaning it may not adjust its heating automatically based on the weather outside.
Your boiler is locking out because it thinks a flame is present inside before it has even tried to ignite.
Your boiler has temporarily stopped working because it cannot accurately read the temperature of the heating system due to a faulty sensor or loose wiring.
Your boiler is having trouble reading the temperature of your hot water supply due to a faulty sensor or loose wiring.
Your boiler has temporarily stopped working because it cannot properly read the temperature of the water returning from your heating system.
Your boiler is getting too hot inside because water isn't flowing through the heating system properly, so it has safely shut down to prevent damage.
Your boiler has temporarily locked out because the internal temperature has dropped dangerously close to freezing, which risks damaging the heat exchanger.
Your boiler has temporarily stopped working because the electricity supply coming into your home has voltage or frequency levels outside of the normal safe operating range.
Your boiler has detected moisture or a positioning issue around the internal ignition sensor, which prevents it from safely lighting the flame.
Your boiler has detected a flame burning inside after it has tried to shut down, which means gas might still be passing through when it shouldn't.
Your boiler is temporarily stopping because water is not flowing properly through the system, which can cause it to overheat.
Your boiler has detected that two internal temperature sensors have been wired up the wrong way around.
Your boiler has detected that a control button has been stuck or held down for too long, which usually happens if a button is physically jammed.
Your boiler has detected that the internal fan responsible for safely pushing out combustion gases is not spinning at the correct speed.
Your boiler has temporarily stopped because the internal exhaust fan is spinning much faster than it is supposed to.
Your boiler has detected an unexpected change in the flow of water through the system, usually caused by a circulation problem or a sticking pump.
Your boiler's electronic settings have been temporarily scrambled by electrical interference, requiring a reset of the system settings.
Your boiler is failing to start up because the main gas valve is taking too long to open, which safely stops the heating from turning on.
Your boiler has gone out because it isn't receiving enough gas or is struggling to push out waste gases properly.
Your boiler's computer memory has been scrambled by electrical interference, which can usually be fixed by simply resetting the system.
Your boiler is failing to keep a stable flame lit during startup, which causes it to safely shut down to prevent gas from building up.
Your boiler has paused because the internal water pressure sensor is reading abnormal levels or needs a moment to stabilize.
Your boiler has stopped working because the water pressure inside the system has risen dangerously high above the safe limit.
Your boiler has stopped working because the pipe that carries away waste water or the flue that removes exhaust gases is blocked, which triggers a safety shutdown.
Your boiler has lost its internal gas calibration settings and needs a professional re-setup before it can safely fire up again.
Your boiler has lost connection to the outdoor temperature sensor, meaning it cannot automatically adjust your heating to match the weather outside.
Your boiler is having trouble communicating with its internal temperature control sensor, which may cause your heating to become erratic or stop working properly.
Your boiler has detected an internal memory error within its main control system, meaning it cannot process its operational settings properly.
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BoilerFaultCodes