36 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has stopped working as a safety precaution due to an internal system failure that prevents it from starting correctly.
Your boiler has tried to light several times but has failed to stay on, so it has locked itself out for safety.
Your boiler’s internal control board is having trouble reading its own data correctly, which prevents the system from starting safely.
Your boiler's computer memory has encountered a processing error, which is preventing the system from starting up safely.
Your boiler is repeatedly struggling to keep the flame lit and has locked itself out for safety.
Your boiler has stopped working because its internal thermometer has developed an electrical fault and can no longer monitor the water temperature accurately.
Your boiler's internal thermometer that monitors the temperature for your radiators has developed a fault and can no longer read the temperature correctly.
Your boiler has detected a failure with the sensor that monitors your hot water temperature, meaning it cannot safely heat water for your taps.
Your boiler has stopped working because the electrical power coming from your home's mains supply is too low for it to operate safely.
Your boiler has detected that the water pressure in the central heating system is too low and it has stopped working as a safety precaution.
Your boiler has detected that the water pressure inside the system is too high, which could cause stress on the internal pipes and components.
Your boiler has stopped working because it cannot detect any water pressure, which means it cannot safely heat your home.
Your boiler has detected an electrical fault with the sensor that monitors exhaust gases, causing the system to shut down for safety.
Your boiler has shut down because it can no longer safely monitor the temperature of the exhaust gases leaving the system.
Your boiler has lost its connection to the sensor that monitors water pressure, meaning it cannot confirm if there is enough water to run safely.
Your boiler has tried to light several times but failed, so it has locked itself for safety.
Your boiler thinks it sees a flame even though it hasn't actually started the ignition process, causing it to shut down for safety.
Your boiler has become too hot and has shut itself down as a safety precaution to prevent damage.
Your boiler has detected an issue with the fan that safely removes exhaust gases, meaning the system has shut down for your safety.
Your boiler is failing to detect the flame it has lit, causing it to shut down as a safety precaution.
Your boiler has stopped working because the internal control board is receiving incorrect signals from the gas valve.
Your boiler's computer memory has encountered a deep internal error and can no longer process instructions safely.
Your boiler has shut down because a temperature sensor is giving inconsistent readings and no longer trusts the data it is receiving.
Your boiler has stopped working because its internal temperature sensors are giving conflicting readings or appear to be stuck, causing the system to shut down for safety.
Your boiler has shut itself down because it has detected a technical error within its electronic control system.
Your boiler has detected an issue with the sensor that monitors the temperature of the water returning to the unit, which is preventing it from heating properly.
Your boiler has shut down because the electrical power reaching it is too weak or unstable to operate safely.
Your boiler has stopped working because it cannot correctly measure the temperature of the water leaving the unit.
Your boiler has detected a problem with the sensor that monitors the waste gases leaving the system, causing it to shut down for safety.
Your boiler has shut itself down for safety after too many failed attempts to reset it remotely or due to a persistent internal fault.
Your boiler has detected that the water pressure in the system is too low to operate safely and has shut down to protect itself.
Your boiler has too much water in the system, which puts unnecessary stress on the internal pipes and seals.
Your boiler has lost its connection to the sensor that monitors water pressure, meaning it cannot confirm if there is enough water to operate safely.
Your boiler is having trouble measuring the temperature of your tap water, which usually means your hot water won't heat up correctly.
Your boiler has shut down because a sensor has detected that the exhaust gases are getting too hot, which is a safety measure to prevent damage.
Your boiler has detected an internal control error and has locked itself out to ensure your safety.
BoilerFaultCodes