22 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has temporarily paused because the water inside has become slightly hotter than it is supposed to be.
Your boiler has temporarily stopped working because a safety device wired into the system, such as a room thermostat or external timer, is signaling that something needs attention.
Your boiler has temporarily paused heating because the radiators are already as hot as the temperature you asked for, but it will automatically turn back on in a few minutes once it cools slightly.
Your boiler has temporarily stopped because it detected that the water inside is getting hotter than the temperature you have set, likely due to poor circulation.
Your boiler has switched itself off because the water inside is heating up too quickly or too unevenly, which often happens when water cannot circulate through your radiators properly.
Your boiler has detected a problem with its internal temperature sensors, meaning it cannot accurately monitor the water temperature and has shut down as a safety precaution.
Your boiler has detected an internal electronic error and has shut itself down to ensure your home's safety.
Your boiler is simply running a standard three-minute safety pause to clear trapped air after a previous glitch, and no action is usually needed.
Your boiler is just taking a temporary three-minute safety pause to clear out trapped air before it attempts to start up again after a previous hiccup.
Your boiler has detected an internal electrical safety fault or a problem with how it is grounded, causing it to shut down to prevent damage.
Your boiler has tried to light itself several times but has failed, likely because there is no gas supply or the ignition part is dirty or broken.
Your boiler is failing to light the flame or keep it running, which means it cannot provide you with heating or hot water.
Your boiler is detecting a flame inside the unit even when it has been instructed to switch off, which indicates a serious internal safety issue.
Your boiler is simply running a standard three-minute safety air-clearing cycle after a previous error before it tries to switch back on.
Your boiler has detected that the internal fan responsible for venting exhaust gases safely is either not spinning or communicating properly, so it has shut down to keep your home safe.
Your boiler is simply running a standard three-minute safety and air-clearing cycle after a previous minor error before it attempts to turn back on.
Your boiler has detected that the internal casing is getting too hot, indicating it is struggling to ventilate correctly or is running too hot internally.
Your boiler has recently experienced an error and is currently running a harmless three-minute safety venting cycle to clear any trapped air before attempting to restart.
Your boiler has detected that some of its internal settings have drifted outside of their safe operating limits, and it has stopped working as a precaution.
Your boiler has detected an internal software or settings error, which is preventing the system from starting up safely.
Your boiler has lost its programmed settings and needs to be reconfigured by a professional to operate correctly.
Your boiler's wall controller is currently overriding normal settings because the built-in frost protection has kicked in to prevent your pipes from freezing during cold weather.
BoilerFaultCodes