50 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has developed a communication problem with its internal memory chip, meaning it does not recognize its own settings and cannot start.
Your boiler's internal memory chip is not communicating correctly with the main control board, meaning the system cannot identify its own settings.
Your boiler thinks it sees a flame even though it hasn't started the ignition process yet, which prevents it from running for safety reasons.
Your boiler is unable to light the flame after several attempts, which means it cannot provide any heating or hot water until the issue is resolved.
Your boiler thinks a flame is present when there shouldn't be one, causing it to shut down for safety purposes.
Your boiler has got too hot and has shut itself down as a safety precaution to prevent damage.
Your boiler has lost power or been turned off while already trying to report a different fault, and it needs a manual restart to identify the original problem.
Your boiler's fan is not spinning or the system cannot detect its movement, which prevents the boiler from starting safely for heating and hot water.
Your boiler has shut down because the exhaust gases are getting too hot, which suggests the internal heat exchanger may be blocked or faulty.
Your boiler is having trouble detecting or controlling the flame, which means it has stopped running for safety reasons.
Your boiler has stopped working because its internal system cannot properly control the flow of gas required to start the flame.
Your boiler's main internal computer has developed a malfunction and is unable to manage the heating process correctly.
Your boiler's internal temperature sensors are giving conflicting information and cannot verify if they are measuring the heat correctly.
Your boiler's internal computer has encountered a critical electronic failure and can no longer control the heating process safely.
Your boiler has detected that the water inside is getting too hot because it isn't moving through the pipes properly.
Your boiler is getting too hot because the water isn't moving through the system properly, causing it to shut down to prevent damage.
Your boiler is having trouble detecting the correct amount of water inside the system, preventing it from running safely.
Your boiler has shut down because it keeps losing water pressure, which usually means there is a leak somewhere in your heating system or a fault within the boiler itself.
Your boiler’s internal computer has encountered a serious communication error and can no longer safely operate.
Your boiler has started an ignition sequence but the flame keeps going out, meaning it cannot stay lit to provide heat or hot water.
Your boiler has detected an electrical fault with the internal sensor that monitors water temperature, causing it to shut down for safety.
Your boiler has lost communication with a sensor that monitors water temperature, causing the system to shut down for safety.
Your boiler has detected a fault with the temperature sensor that monitors your hot water, preventing it from heating correctly.
Your boiler has detected a technical fault with the sensor that monitors your hot water temperature, meaning it cannot heat water accurately.
Your boiler has stopped working because the electrical power coming from your mains supply is too low for it to run safely.
Your boiler is having trouble with the electrical signal coming from your mains power supply, causing it to shut down for safety.
Your boiler has lost communication with its temperature sensor, which means it cannot safely monitor how hot the water is getting and has shut down as a precaution.
Your boiler has detected that the water pressure is too low to operate safely and has shut down as a precaution.
Your boiler's control panel has developed an internal electrical fault and is no longer responding correctly to the reset button.
Your boiler has switched off because there is too much water pressure in the system, which can put unnecessary strain on the internal seals.
Your boiler's internal display screen is having trouble talking to its main computer chip, preventing the unit from starting up.
Your boiler has detected an electrical fault with the internal sensor that monitors water returning to the unit, causing it to shut down for safety.
Your boiler has stopped working because it can no longer monitor the temperature of the water returning from your radiators.
Your boiler has detected an electrical fault with the sensor that monitors exhaust gases, causing the system to shut down for safety.
Your boiler’s internal computer parts are struggling to talk to each other, meaning the display panel cannot send instructions to the main control system.
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 encountered a technical issue that has caused it to shut down for safety, and it likely needs a professional inspection to restart.
Your boiler’s internal computer chip is missing or not communicating properly, meaning the system cannot start up or operate at all.
Your boiler has detected that the water pressure in the system is too low to run safely and has shut down as a precaution.
Your boiler has lit correctly but is struggling to keep the flame burning, causing it to shut down for safety.
Your boiler's internal fan is not spinning or communicating correctly, preventing the system from safely clearing gases so it has shut down for safety.
Your boiler has stopped working because it cannot detect water moving through the system correctly, which is usually caused by a faulty sensor or a blockage.
Your boiler has detected a problem with the sensor that monitors the temperature of the water returning from your radiators, causing the system to stop working for safety.
Your boiler has lost connection with the sensor that measures the temperature outdoors, which may cause your heating to run less efficiently.
Your boiler has stopped working because the electrical supply from the grid or your home's wiring has dropped below the level required for the unit to run safely.
Your boiler’s internal computer has encountered a critical error and can no longer control the heating system safely.
Your boiler has stopped working because it has detected that the water inside it is getting too hot.
Your boiler is failing to keep a flame lit, which means the system has shut itself down for safety and you will not have any heating or hot water.
Your boiler has been manually reset too many times in a short period and has now locked itself out as a safety precaution.
Your boiler thinks it sees a flame even though it hasn't actually started the ignition process yet.
BoilerFaultCodes