24 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected a problem with the burner and has shut itself down for safety, meaning you will have no heating or hot water.
Your boiler has detected a sequence error during the ignition process and has shut down as a safety precaution.
Your boiler's burner has shut down because it isn't receiving enough air or fuel to ignite safely, meaning you will have no heating or hot water until it is fixed.
Your boiler's burner has stopped working correctly because it is failing to receive enough fuel or cannot successfully ignite.
Your boiler has detected an internal safety issue and has shut itself down to prevent damage or unsafe operation.
Your boiler has detected a sequence error during the ignition process and has shut down for safety to prevent a gas buildup.
Your boiler has disabled the burner for safety reasons because it is failing to ignite or detect a flame properly.
Your boiler is getting too hot and has shut down as a safety precaution to prevent damage.
Your boiler is stuck in a self-testing loop, which means it cannot start the normal heating process.
Your boiler has failed to fire up, meaning you likely have no heating or hot water because the system cannot establish a flame.
Your boiler has detected trapped air inside the system and is currently trying to clear it out to prevent the burner from overheating.
Your boiler has detected that the pump is and not moving water through the system as it should, or there is air trapped inside preventing it from working.
Your boiler has detected that the internal pump is either jammed or it is not sensing enough water pressure to circulate safely.
Your boiler is struggling to manage its settings automatically and has switched to a basic backup mode to keep your home warm until it can be adjusted.
Your boiler is operating in a manual override or temporary control mode, often meaning it is ignoring external thermostat signals to keep the heating running.
Your boiler has stopped working because the internal control computer has encountered a critical error or does not recognise its configuration card.
Your boiler is still providing heat but cannot accurately monitor the temperature of the water flowing into your heating system from a specific secondary pipe.
Your boiler has stopped heating because the burner has shut down to prevent damage, often due to a communication error between the internal components.
Your boiler has shut down because the internal fan which clears waste gases is not spinning at the correct speed.
Your boiler is continuing to work but cannot accurately measure the water temperature in a specific part of your system, usually meaning your heating might not be as efficient or consistent as usual.
Your boiler is operating in a manual or forced constant-temperature mode, usually because it has lost its normal external settings or weather sensors.
Your boiler has automatically activated its frost protection mode because the outside temperature has dropped to freezing point.
Your boiler is working exactly as it should and there is no fault detected.
Your boiler has switched to a protective mode because the outdoor temperature has dropped to freezing, causing it to run the heating pump continuously to prevent pipes from freezing.
BoilerFaultCodes