21 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected an internal issue and is showing a specific error number on the screen to help identify the problem.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler is trying to start but keeps failing to keep the flame lit, so it has shut down as a safety precaution.
Your boiler has detected an issue with the fan that safely clears exhaust gases, preventing it from starting up for your safety.
Your boiler has sensed a problem with its internal temperature sensors or a lack of water movement, causing it to shut down for safety.
Your boiler has detected a sensor problem that means it cannot accurately measure the temperature of the water returning to the unit, causing it to shut down for safety.
Your boiler is having trouble reading the outdoor temperature, which it uses to help run your heating more efficiently.
Your boiler is not receiving enough electrical power from the grid to operate safely and has shut down as a precaution.
Your boiler's main electronic control system has lost its memory or settings, meaning it cannot figure out how to operate safely.
Your boiler's main electronic brain has lost its memory or suffered a major internal fault, meaning it has completely stopped working to keep you safe.
Your boiler has lost its flame while trying to run, which means it cannot heat your water or your radiators.
Your boiler has detected that heat is building up too quickly and cannot circulate around your home, likely due to a blockage or a pump failure.
Your boiler has switched itself off because the internal water temperature has become too hot, usually caused by a lack of water flow through the system.
Your boiler has failed to light several times and has shut down for safety, meaning you currently have no heating or hot water.
Your boiler has sensed a problem with its internal temperature sensors or a lack of water movement, causing it to shut down for safety.
Your boiler has detected a sensor problem that means it cannot accurately measure the temperature of the water returning to the unit, causing it to shut down for safety.
Your boiler thinks a flame is burning even though it shouldn't be, causing the system to shut down for safety.
Your boiler's main electronic brain has lost its programming or failed entirely, meaning it can no longer run safely.
Your boiler's main electronic brain has lost its programming or suffered an internal fault and needs to be reset or replaced by an engineer.
Your boiler has attempted to restart itself too many times in a short period because it is detecting a recurring problem.
Your boiler has lost its flame while running, meaning it is not getting enough gas or the spark is failing to keep the burner lit.
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BoilerFaultCodes