33 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler thinks it sees a flame when it shouldn't, which is a safety check that prevents the system from starting up.
Your boiler has detected an electrical fault within its internal wiring which has caused the system to shut down for safety.
Your boiler is failing to light properly or cannot detect that a flame has started, resulting in a safety shutdown to prevent unburnt gas from building up.
Your boiler has encountered a technical communication error between its internal controls, causing it to shut down for safety.
Your boiler is struggling to breathe properly because air isn't moving through the system as it should.
Your boiler has lost power to its main control system because an internal safety fuse has blown.
Your boiler has shut down because the water inside has become or is being detected as dangerously hot.
Your boiler has shut down because the water returning from your heating system is too hot, which prevents the unit from cooling itself down properly.
Your boiler has stopped working because it thinks the internal water temperature readings are the wrong way around or flowing incorrectly.
Your boiler has shut down because the water inside it is heating up too quickly, which usually means the water isn't moving through the system properly.
Your boiler's fan is not spinning correctly, which means the system cannot safely vent exhaust gases and has shut down as a precaution.
Your boiler's fan is spinning continuously and cannot stop itself, which prevents the heating system from starting its normal cycle.
Your boiler has shut down because the water is heating up too quickly or isn't circulating properly through the system.
Your boiler has detected an electrical fault with the internal sensor that monitors the water temperature, causing the system to shut down for safety.
Your boiler has detected an electrical fault with the internal sensor that monitors the temperature of the water returning to the unit, causing it to stop running for safety.
Your boiler has stopped working because it cannot accurately measure the temperature of the water leaving the unit.
Your boiler has detected a problem with the sensor that monitors the temperature of the water returning to the unit, causing it to stop running for safety.
Your boiler has stopped working because it cannot correctly measure the temperature of the water returning to the unit.
Your boiler's computer settings have become scrambled or are outside of their safe operating range, causing the system to stop working.
Your boiler is unable to start because it cannot confirm that the internal fan system is safe to move air through the flue.
Your boiler is displaying its current operational mode setting, which tells you whether the heating and hot water have been intentionally switched on or off.
Your boiler's main internal computer has developed a technical error and is unable to manage the heating system safely.
Your boiler's electronic brain has lost power, meaning the system cannot run or communicate with the controls.
Your boiler is failing to light the gas or cannot stay lit, which means it will stop providing heat and hot water for your property loop.
Your boiler has switched itself off because it has reached a temperature that is too high, often caused by a circulation problem or a blockage.
Your boiler has detected an issue with the sensors that monitor water temperature, which is preventing the system from heating up safely.
Your boiler's main internal computer has developed a malfunction and is unable to manage the heating process safely.
Your boiler has shut down because it has detected a problem with the air flow or the way exhaust gases are being cleared from the system.
Your boiler has sensed that the water inside is getting too hot and has shut down to prevent damage.
Your boiler has stopped working because the internal fan used to clear out waste gases is not spinning at the correct speed.
Your boiler has detected that water isn't moving through the system correctly or is overheating too quickly, causing it to shut down to prevent damage.
Your boiler is struggling to light or keep its main flame burning steadily, which is preventing it from heating properly.
Your boiler is failing to light properly because the internal pilot flame is being lost or is too weak to stay on.
BoilerFaultCodes