23 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 stopped working because its main computer control board is either improperly configured or has experienced a major electrical fault.
Your boiler has lost its programmed settings or experienced an internal electrical fault, meaning it cannot operate safely and must be shut down.
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 failed to ignite after multiple attempts and has safely locked itself out to prevent any issues.
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 has temporarily stopped because it cannot detect the temperature rising properly when trying to heat up.
Your boiler has stopped working because its main computer control board is not properly set up or has suffered an electrical fault.
Your boiler has stopped working because its main computer control board has lost its programming or experienced an electrical fault.
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