24 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Baxi 800 Combi
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Your boiler's temperature sensor for the heating system is not sending a proper signal, causing the boiler to stop working to protect itself.
Your boiler has detected a problem with the sensor that monitors the temperature of the exhaust gases exiting your home, preventing it from firing safely.
Your boiler is currently unable to accurately read the temperature of the water returning to it, so it has shut down to prevent potential overheating.
Your boiler's computer has encountered an internal error that it does not recognise, causing it to shut down for safety reasons.
Your boiler is struggling to move water through the system effectively, which is causing it to shut down to prevent overheating.
Your boiler has detected an issue with the temperature sensor that monitors the water heat, causing it to shut down for safety.
Your boiler has detected that it is overheating and has automatically shut down to prevent damage because the internal pump is not moving water correctly.
Your boiler has detected an internal error with its main control system that is preventing it from operating correctly.
Your boiler has detected that it is getting too hot and has automatically shut itself down to prevent damage.
Your boiler has detected that the water pressure inside your heating system is too high, causing it to shut down for safety.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler is struggling to move water around your heating system effectively, preventing it from heating your home or water properly.
Your boiler is failing to move hot water around your radiators, likely because the internal pump is blocked, seized, or air is trapped in the system.
Your boiler has attempted to start but failed to light the flame, which means it has temporarily stopped working to stay safe.
Your boiler has detected that the flue gases are getting too hot, so it has safely shut itself down to prevent any damage.
Your boiler has stopped working because it failed to light the flame needed to produce heat.
Your boiler is trying to start but cannot detect a flame, likely because the gas supply is blocked or the ignition system has failed.
Your boiler is trying to start but the flame is not catching, so it has shut down as a safety precaution.
Your boiler has attempted to light the gas flame multiple times but has failed, so it has safely shut down to prevent gas from escaping.
Your boiler has stopped working because it cannot properly clear exhaust gases, which is a safety mechanism to prevent harmful fumes from building up.
Your boiler has detected that the internal fan responsible for safely venting exhaust gases is not working or communicating correctly, so it has shut down to prevent unsafe operation.
Your boiler is struggling to accurately measure the temperature of the water used for your taps and shower, which is causing it to stop producing hot water.
Your boiler has detected a flame inside the unit when it should be switched off, so it has shut itself down to ensure your safety.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
BoilerFaultCodes