80 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has tried to light several times but failed, so it has locked itself for safety.
Your boiler has switched itself off because it has detected that the water inside has become too hot.
Your boiler has stopped working to prevent a technical fault from causing damage, essentially 'tripping' itself off like a fuse.
Your boiler has stopped working because the water pressure is either too low, too high, or the water isn't moving through the system correctly.
Your boiler has detected an issue with the ventilation fan, which means it cannot safely clear exhaust fumes and will not ignite.
Your boiler has detected a fault with the sensor that monitors the temperature of the water leaving the unit to heat your radiators.
Your boiler is struggling to accurately measure the temperature of your hot water due to a faulty internal sensor.
Your boiler's outside temperature sensor has failed, meaning the system doesn't know how hard it needs to work to heat your home based on the weather.
Your boiler has shut down because it has detected an unsafe build-up of heat or exhaust gases in the flue system.
Your boiler is detecting a flame when it shouldn't be there, which is a safety mechanism that prevents the system from starting up.
Your boiler has detected a problem with the sensor that monitors the temperature of the water coming back from your radiators, preventing it from heating your home safely.
Your boiler has detected that the water is heating up too quickly or not circulating properly, causing the system to shut down to prevent overheating.
Your boiler has likely overheated because water is not circulating properly through the system.
Your boiler is struggling to move water through the system correctly, which is causing it to shut down to prevent overheating.
Your boiler has sensed that the exhaust gases are getting too hot and has shut down as a safety precaution.
Your boiler has detected that the water isn't heating up or circulating correctly immediately after starting, causing it to shut down for safety.
Your boiler has detected a problem with one of its internal monitoring sensors, which is preventing the system from operating correctly.
Your boiler has detected an internal electronic failure and has shut down for safety because it cannot correctly control the gas valve.
Your boiler has stopped working because its internal safety computer cannot correctly control the gas valve, meaning the boiler has locked itself out for safety.
Your boiler has detected a flame that continues to burn even after the gas valve should have closed, which is a safety fault that requires a professional inspection.
Your boiler is unable to control the flame size properly because a key electronic connection to the gas control system has failed.
Your boiler has sensed a blockage or issue with the flue pipe that safely carries exhaust fumes out of your home, causing it to shut down for safety.
Your boiler is failing to keep the flame lit and has locked itself out after several unsuccessful attempts to stay running.
Your boiler has detected that its internal temperature sensors are giving very different readings, causing the system to shut down for safety.
Your boiler has detected an issue with the electrical power timing reaching the unit, which is preventing it from running safely.
Buttons on the control panel appear to be stuck or are not communicating correctly with the boiler's internal computer.
Your boiler has stopped working because the water pressure is too low or it is struggling to light the burner.
Your boiler is having trouble talking to its smart thermostat or external controller, meaning it may not receive instructions to turn the heating on.
Your boiler needs to perform an automatic self-calibration of its gas valve and combustion settings to ensure it operates efficiently.
Your boiler is struggling to maintain a stable flame because the internal controls are detecting that the gas is not burning correctly.
Your boiler is struggling to get enough gas to stay lit, which has caused it to stop working as a safety precaution.
Your boiler's internal computer has lost its settings and cannot correctly control the power of the burner.
Your boiler is struggling to get enough gas to stay lit, which has caused it to stop working for safety reasons.
Your boiler's electronic brain is struggling to properly manage the heat output, which usually means it cannot control the gas flow correctly.
Your boiler's internal computer has encountered a technical glitch or an issue with the electrical power coming into your home.
Your boiler has stopped working because it has been reset too many times in a short period and has now locked itself for safety.
Your boiler has detected an issue with the electrical power supply coming into your home, meaning the electrical timing does not match what the boiler requires to run safely.
Your boiler has repeatedly encountered multiple safety or operational errors, causing it to lock itself out for protection.
Your boiler is not receiving the correct amount of electrical power to operate safely and has shut down as a precaution.
The internal computer in your boiler has lost its settings and does not know how to operate the unit correctly.
Your boiler has temporarily stopped working because it failed to ignite safely.
Your boiler has temporarily stopped working as a safety precaution due to an internal lock-out, meaning you currently have no heating or hot water.
Your boiler has safely shut itself down because it cannot detect a proper flame or exhaust the waste gases correctly.
Your boiler has temporarily stopped working for safety reasons, usually because it cannot detect a flame or has lost water pressure.
Your boiler has safety-locked itself because it is having trouble detecting or maintaining a flame.
Your boiler has safely shut itself down due to a general internal error and requires a manual reset or professional attention to get running again.
Your boiler has safely locked itself out and stopped working because it has detected a safety or operational fault that needs attention.
Your boiler has temporarily shut itself down for safety because it has detected a recurring operational issue.
Your boiler has safely shut itself down because it has detected a safety lockout, meaning it will not produce heat or hot water until the issue is cleared.
Your boiler has safely locked itself out to prevent a potential hazard, meaning you currently have no heating or hot water.
Your boiler has safely shut itself down due to a general safety lock-out, meaning it has stopped working until the underlying issue is cleared.
Your boiler has completely stopped working and locked itself out for safety reasons due to an internal fault.
Your boiler has temporarily stopped working and locked itself out as a safety precaution due to an internal fault.
Your boiler has temporarily stopped working for safety reasons and needs to be reset.
Your boiler has safely shut itself down due to a safety lock-out, meaning it has temporarily stopped working to prevent potential hazards.
Your boiler has completely stopped working and locked itself for safety due to a persistent internal fault.
Your boiler has completely stopped working and locked itself for safety due to a recurring operational fault that it cannot clear on its own.
Your boiler has safely locked itself out to prevent damage because it cannot ignite properly.
Your boiler has temporarily shut down and locked itself for safety due to a failure to ignite or a detected system error.
Your boiler has safely shut itself down due to a safety lock-out, meaning it has stopped working until the underlying issue is resolved.
Your boiler has safely shut down and locked itself to prevent operation due to a safety fault.
Your boiler has safely shut itself down due to a safety lock-out, meaning it needs to be manually reset or checked by a professional.
Your boiler has temporarily stopped working for safety reasons and needs to be reset.
Your boiler has temporarily stopped working and locked itself out for safety, meaning you currently have no heating or hot water.
Your boiler has completely stopped working and locked itself out as a safety precaution due to a persistent internal fault.
Your boiler has completely stopped working and locked itself out for safety because it has detected an internal fault that it cannot resolve on its own.
Your boiler has completely stopped working and locked itself out for safety, meaning you currently have no heating or hot water.
Your boiler has temporarily stopped working and locked itself for safety due to a general fault it has detected.
Your boiler has completely stopped working and locked itself out for safety because it has detected an internal fault that it cannot clear on its own.
Your boiler has completely stopped working and locked itself down for safety reasons.
Your boiler has safely shut itself down due to a safety lock-out, meaning it has stopped working until the underlying issue is resolved.
Your boiler has completely stopped working and locked itself out for safety reasons due to a serious internal fault.
Your boiler has completely stopped working and locked itself out for safety, meaning you currently have no heating or hot water.
Your boiler has safely shut itself down due to a safety lock-out, meaning it needs to be manually reset or inspected by a professional before it can run again.
Your boiler has completely stopped working and locked itself down for safety because it has detected a serious internal fault.
Your Biasi boiler has completely stopped working and locked itself out for safety reasons.
Your boiler has temporarily stopped working and locked itself out as a safety precaution due to a general operational failure.
Your boiler has suffered a safety lock-out and stopped working to protect itself and your home.
Your boiler has completely stopped working and locked itself out for safety reasons due to an internal fault or safety system trigger.
Your boiler is struggling to keep the water at the right temperature while you are running a hot tap, causing it to protect itself by switching off.
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BoilerFaultCodes