53 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is failing to light the burner, meaning it cannot provide you with any heating or hot water.
Your boiler is failing to detect a flame, so it has safely shut down to prevent the release of unburnt gas.
Your boiler has switched itself off because it has detected dangerously high temperatures, likely caused by a disruption in the flow of water circulating through your radiators.
Your boiler has detected that the internal fan responsible for safely removing exhaust gases is not spinning at the correct speed, causing the system to stop for safety reasons.
Your boiler has detected that the exhaust gases are becoming dangerously hot, so it has safely shut itself down to prevent damage.
Your boiler has detected an electrical fault in the system that controls the gas supply, meaning it cannot safely start up to provide heat or hot water.
Your boiler's temperature sensors are giving conflicting readings, causing the system to stop operating to prevent potential damage.
Your boiler is struggling to heat the water quickly enough, so it has stopped working to prevent itself from overheating.
Your boiler is struggling to detect the expected temperature increase in the water flowing back to it, likely due to a circulation or sensor issue.
Your boiler has detected an unusual and rapid change in water temperature, causing it to shut down for safety reasons to prevent overheating.
Your boiler's central control computer has encountered an internal error and cannot communicate properly, meaning the system has shut down for safety.
Your boiler is struggling to detect the flow of water because of a faulty electrical connection inside the unit, meaning it will likely refuse to heat your water.
Your boiler has detected that a temperature reading from its internal water system is not what it expects, meaning it has safely shut down to prevent damage.
Your boiler is experiencing a generic system error that is not linked to a specific recognized fault, often indicating a temporary electronic hiccup.
Your boiler is currently unable to read the water temperature correctly because of a faulty internal sensor connection, which has caused it to stop heating your home as a safety precaution.
Your boiler is struggling to accurately measure the temperature of the water returning to it, which causes it to stop operating to stay on the safe side.
Your boiler is having trouble communicating with its internal temperature sensors, which means it cannot accurately measure how hot the water is and has stopped working as a safety precaution.
Your boiler is unable to confirm that the burner has successfully lit, so it has safely shut itself down to prevent gas buildup.
Your boiler has detected an issue with the system that lights the flame, meaning it cannot safely ignite to produce heat or hot water.
Your boiler has locked itself for safety after too many unsuccessful restart attempts in a short period of time.
Your boiler's central control computer is experiencing a critical internal failure and has stopped the system from operating to prevent further damage.
Your boiler has detected a faulty connection in the part that measures the temperature of your hot water, which is preventing it from heating your taps correctly.
Your boiler is struggling to detect the temperature of the water being heated for your taps, which means it has safely shut down to prevent overheating.
Your boiler is struggling because the electricity supply it is receiving is weaker than it should be.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler has detected an issue with the sensor that monitors the temperature of the gases leaving your system, which is preventing it from firing up safely.
Your boiler has detected that the exhaust temperature is being measured incorrectly and has shut itself down as a safety precaution.
Your boiler's temperature sensors are giving conflicting readings, causing the system to stop operating safely to prevent potential overheating.
Your boiler is struggling to talk to the control system or other connected units, causing it to pause operations to prevent errors.
Your boiler is struggling to talk to another heating unit connected to it, which is preventing the system from operating correctly.
Your boiler has failed to light the flame needed to heat your water and home, so it has automatically shut down for safety.
Your boiler has detected that it is running too hot and has automatically turned itself off to prevent any damage or danger.
Your boiler has detected an issue with the ventilation system that clears away exhaust fumes, so it has safely shut itself down to prevent any risk.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
Your boiler's temperature sensor is providing incorrect readings, which prevents the unit from heating your water or home safely.
Your boiler is struggling to accurately measure the temperature of the hot water it provides, which will likely result in the water being too cold or not heating up at all.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
Your boiler is struggling to accurately measure the temperature of the water inside your hot water cylinder, which means it may fail to heat your water properly.
Your boiler is struggling to accurately measure the temperature of the water returning to it, so it has stopped heating to prevent potential overheating.
Your boiler has stopped working because the internal component responsible for pushing exhaust gases out of your home is not operating correctly.
Your boiler is detecting a flame inside the unit even when it shouldn't be running, which is a safety concern that prevents it from starting.
Your boiler's control panel has detected that one of the buttons or switches is either stuck or not responding correctly, which is preventing the system from operating.
Your boiler has lost its connection to the remote wall controller, meaning it cannot receive signals to adjust your heating or hot water settings.
Your boiler has detected that the electricity supply coming into your home is temporarily too low for it to operate safely, causing it to shut down to prevent damage.
Your boiler has stopped working because the flame inside has gone out and will not stay lit.
Your boiler is repeatedly struggling to stay lit and has shut itself down as a safety precaution.
Your boiler is struggling to pump water around your heating system correctly, which is preventing it from working as it should.
Your boiler is struggling to move heat from the unit into your radiators quickly enough, causing a significant temperature difference that has triggered a safety shutdown.
Your boiler is experiencing a communication error between its internal electronic parts, meaning it has stopped working to prevent further damage.
Your boiler's main control panel is failing to process information correctly, which has caused it to shut down for safety.
Your boiler is having trouble reading the temperature of the water flowing through your system because of a faulty connection or sensor.
Your boiler is struggling to detect the outside temperature, so it is temporarily running on a backup setting to keep your home warm.
Your boiler's internal computer system is currently confused and cannot communicate correctly, meaning the unit will not start until it is digitally reconfigured.
BoilerFaultCodes