37 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Inovia
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Your boiler has detected that the water temperature has reached an unsafely high level, causing it to shut down to prevent damage.
Your boiler has failed to light the gas flame and has shut down as a safety precaution.
Your boiler has switched itself off because it is detecting that the water inside has become far too hot.
Your boiler has shut down because it has detected that it is overheating or there is an issue with how the exhaust gases are being monitored.
Your boiler has stopped working because the water pressure is too low or the water isn't moving through the system properly.
Your boiler has detected a problem with the fan that safely removes exhaust gases, meaning the system has shut down for safety.
Your boiler's central heating sensor is sending an incorrect signal, which means the system cannot accurately measure how hot the water is for your radiators.
Your boiler is struggling to measure the temperature of your hot water, which usually means it cannot provide a consistent hot water supply.
Your boiler has detected a problem with the sensor that monitors the temperature of the exhaust gases, causing the system to shut down for safety.
Your boiler thinks it sees a flame even though it hasn't actually started the burning process yet, which is causing it to shut down for safety.
Your boiler is struggling to detect when you turn on a hot tap, meaning you might have inconsistent or no hot water.
Your boiler has detected an issue with the system that safely manages air flow and exhaust fumes, causing it to shut down for safety.
Your boiler has stopped working because it has detected a serious internal communication or electrical safety error that requires a professional inspection.
Your boiler has sensed it is getting too hot and has shut down as a safety precaution to prevent damage.
Your boiler has stopped working because it has detected a problem with the internal electronics or the way part of its wiring is communicating.
Your boiler has failed to light or has lost its flame, which has caused it to lock itself out for safety.
Your boiler has overheated, prompting a safety shutdown to protect the internal components.
Your boiler has detected a problem with how it disposes of waste gases or how it brings in fresh air, causing it to shut down for safety.
Your boiler has detected low water pressure in the system, which has caused it to shut down to prevent damage.
Your boiler has stopped working because it cannot safely verify that the fan is moving harmful exhaust fumes out of the flue.
Your boiler has failed to light or cannot detect a flame, meaning it will not provide heating or hot water until the issue is resolved.
Your boiler is failing to light the gas flame required to heat your water and home.
Your boiler has stopped working because it has detected that the water inside the system has become too hot.
Your boiler is trying to start but cannot light the gas flame, causing it to shut down for safety.
Your boiler has detected that the water pressure is too low to operate safely.
Your boiler has overheated, causing it to shut down automatically for safety.
Your boiler has lost track of how hot the water is in your radiators, so it has shut down to avoid overheating.
Your boiler has stopped working because a sensor that monitors the temperature of the exhaust gases has detected a fault or is broken.
Your boiler has stopped working because the water pressure is too low for the system to run safely.
Your boiler has stopped working because water is not moving around the system properly, which has caused it to shut down to prevent overheating.
Your boiler has detected a problem with how it breathes or clears waste gases, preventing it from firing up for your safety.
Your boiler is failing to light the gas burner, meaning you will not have any heating or hot water until the system is reset or repaired.
Your boiler has switched itself off because it got too hot, which is a safety mechanism to prevent damage.
Your boiler has shut down because a sensor has detected that the exhaust gases are too hot or the sensor itself has failed.
Your boiler is not detecting a flame, which means it has stopped working as a safety precaution to prevent unburnt gas from building up.
Your boiler is failing to detect a flame, which means it cannot light safely to provide you with heating or hot water.
Your boiler is not receiving electrical power or the main control computer inside has failed, causing the system to shut down completely.
BoilerFaultCodes