24 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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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 has detected an internal communication error or a electrical fault in its main control system, meaning it has safely shut down to prevent damage.
Your boiler's main control board is stuck in a special programming mode rather than operating normally to heat your home.
Your boiler has detected that the water is flowing in the wrong direction through the pipes or that the temperature sensors have been installed on the wrong pipes.
Your boiler has stopped heating because water is not moving through the system properly.
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 temporarily locked itself out because the water inside is getting too hot or is not flowing properly.
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 is temporarily shutting down because it is not detecting the expected temperature increase when it tries to heat up.
Your boiler's electronic control system has lost its settings or is failing to communicate properly, which means the boiler cannot safely start up.
Your boiler has stopped working because its internal computer has lost its settings or detected an electrical problem with the gas control.
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.
Your boiler's main control board has accidentally entered its factory setup mode rather than running normally to heat your home.
Your boiler's main control board has accidentally entered its programming setup mode rather than running normally.
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BoilerFaultCodes