34 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Quantom
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Your boiler has disabled the reset button because it was pressed too many times in a short period, likely due to an underlying fault causing repeated lockouts.
Your boiler’s internal computer is having trouble processing signals from its electronic sensors, which has caused the system to stop working for safety.
Your boiler's internal computer parts are having trouble communicating because they are running mismatched software programs.
Your boiler is repeatedly struggling to keep the flame lit and has safely shut down to prevent damage.
Your boiler has detected a fault with the sensor that monitors air temperature within the ducting, causing it to stop running for safety.
Your boiler has lost its connection to the sensor that monitors air temperature inside the ducting, causing the system to stop working for safety.
Your boiler is not receiving the correct amount of electricity from your home's power supply to operate safely.
Your heater has stopped working because its internal temperature sensor has developed an electrical fault and can no longer read the air flowing back into the unit.
Your boiler has detected an electrical fault with the internal sensor that monitors exhaust gases, causing it to shut down for safety.
Your boiler has shut down because it cannot detect the sensor that monitors the temperature of the exhaust gases.
Your boiler has sensed that the air it is heating is getting too hot and has shut down as a safety precaution.
Your boiler's main internal computer is having trouble talking to the screen on the front, meaning the controls might not respond correctly.
Your boiler’s internal computer chip has encountered an error and is unable to communicate properly with the rest of the unit.
Your boiler is struggling to detect the correct electrical power supply required to operate safely.
Your boiler has stopped working because the fan that circulates air is spinning at the wrong speed, causing the system to shut down for safety.
Your boiler has stopped working because the internal fan that clears away waste gases is spinning at the wrong speed.
Your boiler has temporarily stopped working because it cannot properly check that the fan is moving air and waste gases through the system.
Your boiler is waiting for the internal fan to reach the correct speed before it can safely start the ignition process.
Your boiler has failed to light the gas flame after several attempts, meaning it cannot provide you with any heating or hot water until reset.
Your boiler thinks it sees a flame even though it hasn't finished its startup sequence yet, so it has shut down for safety.
Your boiler has shut down because its internal temperature has gotten too hot, and it has triggered a safety cut-out to prevent damage.
Your boiler has stopped working because it cannot confirm that the fan is safely clearing waste gases from the system.
Your boiler has detected that a safety sensor is stuck in the 'on' position, preventing the system from starting its ignition sequence safely.
Your boiler has lost its ability to measure the temperature of the air returning to the unit, so it has stopped heating for safety.
Your boiler has detected a problem with the sensor that monitors the exhaust gases, which has caused the system to shut down for safety.
Your boiler is failing to detect the flame that heats your water, causing the system to shut down for safety.
Your boiler has detected an internal electrical problem with the component that controls the gas flow, meaning it cannot ignite safely for heating or hot water.
Your boiler has stopped working because the internal drainage pump cannot clear the water it produces, causing a backup that has shut the system down for safety.
Your heater has detected a problem with the fan that circulates warm air around your home, meaning the unit cannot safely push heat through your vents.
Your boiler's internal computer has encountered a processing error and can no longer control the heating system safely.
Your boiler’s internal computer has encountered a memory error and can no longer process its instructions correctly.
Your boiler’s internal computer has suffered a technical failure and can no longer safely control the heating process.
Your boiler has sensed that the exhaust gases are getting too hot and has shut down as a safety precaution.
Your heater is temporarily turning itself off because it is getting too hot and needs to cool down to prevent damage.
BoilerFaultCodes