26 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Baxi 800
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Your boiler has lost communication with the sensor that monitors the weather outside, meaning it may not heat your home as efficiently as usual.
Your boiler is struggling to monitor its temperature correctly because a internal sensor is sending a faulty signal, preventing the heating from working properly.
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 has detected a problem with the sensor that monitors the temperature for your taps, meaning you may have inconsistent or no hot water.
Your boiler has switched itself off because it has become too hot internally and needs to cool down for safety.
Your boiler has stopped working because the water pressure in the system has dropped too low and needs topping up.
Your boiler has detected that water is not moving through the system correctly, which could be due to a blockage or a pump failure.
Your boiler has shut itself down because the exhaust gases have reached a temperature that is too high, which is a safety feature to prevent damage.
Your boiler has shut down because the exhaust gases have reached a dangerously high temperature, triggering a safety sensor to prevent damage.
Your boiler has failed to light, which is usually caused by a temporary interruption in the gas supply or a frozen condensate pipe.
Your boiler's computer control board has developed a fault and can no longer communicate with the system components, causing the unit to shut down for safety.
Your boiler’s internal computer has developed a fault and is struggling to process information correctly.
Your boiler has stopped working because the fan that clears away waste gases is not spinning correctly or has lost communication with the control board.
Your boiler has stopped working because the fan used to clear out waste gases is not spinning at the correct speed or has failed to start.
Your boiler has detected a problem with the sensor that monitors your hot water temperature or a switch that controls water flow, which usually means your hot water will stop working properly.
Your boiler's internal computer has developed a fault and can no longer control the heating or hot water safely.
Your boiler has detected an internal electrical error that is preventing it from running safely, and it usually means the main control board is confused or failing.
Your boiler is struggling to move water around the system properly, which is causing it to shut down to prevent overheating.
Your boiler has detected a safety issue and stopped working to protect itself, meaning you currently have no heating or hot water active.
Your boiler has stopped working for safety reasons and needs a manual reset because it cannot successfully get the flame started or stay lit.
Your boiler has switched itself off for safety reasons because it cannot light its flame or has become too hot to operate.
Your boiler has stopped working because the amount of water inside your heating system has dropped below the required level.
Your boiler is receiving power as normal and this light simply confirms it is switched on, not indicating a fault.
Your boiler has stopped working because its small pilot flame has gone out, meaning it cannot ignite the main burners to heat your home or water.
Your boiler has stopped working because the internal flame that keeps it running has gone out and will not stay lit.
Your boiler has stopped working and needs a manual restart to try and clear a temporary internal error.
BoilerFaultCodes