23 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has lost power to its internal electronics, likely caused by a safety fuse blowing or an electrical fault inside the unit.
Your boiler has likely experienced an internal electrical fault or a component failure that has caused a safety fuse on the main control board to blow.
Your boiler has stopped working because the internal fan, which safely exhausts fumes, isn't starting up.
Your boiler is struggling to start up properly because the main internal computer is failing to control the fan correctly.
Your boiler is struggling to maintain a steady fan speed, which is preventing it from completing its startup sequence and heating your home.
Your boiler is failing to ignite the main gas burner, which means you will have no heating or hot water until it is repaired.
Your boiler has detected an electrical supply issue, likely caused by a tripped switch, a blown fuse, or a temporary power failure.
Your boiler has lost electrical power, which is usually caused by an issue with the mains supply or a blown internal fuse.
Your boiler is not receiving electrical power or has an internal blown fuse, meaning it cannot start the ignition process.
Your boiler has detected that the water pressure is too low to operate safely, causing it to lock out.
Your boiler has become too hot and has automatically shut down for safety purposes.
Your boiler has switched itself off because it has reached an unsafe temperature or it has detected a faulty component in its safety system.
Your boiler has detected an internal electrical communication fault which is preventing it from starting up safely.
Your boiler has stopped working because it cannot safely clear away waste gases, preventing it from firing up.
Your boiler is unable to safely clear exhaust fumes, which prevents it from firing up to provide heat or hot water.
Your boiler is failing to light the small internal flame needed to start the main burner, which means your heating and hot water will not work.
Your boiler is failing to light the gas flame or cannot detect that the flame has started, so it has shut down for safety.
Your boiler is failing to light the gas or cannot confirm that a flame is present, meaning the system has shut down for safety.
Your boiler has lost power because of an electrical issue or a blown fuse inside the control unit.
Your boiler has switched itself off because it has either become too hot or the water pressure in the system has dropped too low.
Your boiler has stopped working because it cannot safely confirm that the fan is clearing exhaust gases from the system.
Your boiler is attempting to start but cannot successfully light or detect a steady flame, so it has shut down for safety.
Your boiler is failing to start up because the small ignition flame is not lighting correctly.
BoilerFaultCodes