18 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has suffered a major electrical failure where the internal fuse blows instantly, meaning the main control board has likely short-circuited and stopped working.
Your boiler has failed to ignite the gas needed to heat your home, which has triggered a safety shutdown.
Your boiler is failing to light the burner because it cannot detect a flame or spark, meaning you currently have no heating or hot water.
Your boiler has detected an issue with the internal ventilation system that removes exhaust gases, so it has automatically stopped working to keep your home safe.
Your boiler is failing to ignite because it cannot receive the gas supply required to produce a flame.
Your boiler's temperature sensor is providing an incorrect reading or has disconnected, which prevents the system from safely heating your water.
Your boiler has detected that the water temperature is rising too quickly or overheating, suggesting that internal parts are struggling to move heat away from the burner efficiently.
Your boiler's internal tank that handles pressure changes is likely losing its charge or leaking, which can lead to system pressure spikes.
Your boiler's electronic brain is failing to communicate correctly with its internal switches, preventing it from safely starting up.
Your boiler's electronic control system is failing to receive the correct power supply, preventing it from safely starting up for heating or hot water.
Your boiler's water pump is unable to circulate water effectively, meaning your heating and hot water will stop working.
Your boiler is failing to confirm that the exhaust fan is working properly, so it has shut down to ensure your safety.
Your boiler has identified an issue with the internal water flow, meaning it cannot circulate heat correctly to your radiators or taps.
Your boiler is struggling to switch between heating your radiators and heating your hot water taps, which may cause your hot water to stop working or your radiators to get hot when they shouldn't.
Your boiler is struggling to detect the correct water pressure needed to run, likely due to a faulty sensor reading.
Your boiler is struggling to detect when you turn on a hot tap, which means you may have no hot water or the water temperature might stay cold.
Your boiler is struggling to detect the flow of water needed to provide hot water to your taps, usually due to a faulty sensor or internal blockage.
Your boiler has detected that the internal safety system which manages water pressure is leaking, meaning the boiler has temporarily shut down to prevent water damage.
BoilerFaultCodes