BoilerFaultCodesYour boiler is not receiving electrical power correctly or there is a wiring issue preventing it from starting.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Power supply or polarity problem (Not lit)
What causes this fault?
This fault occurs when the boiler is unable to detect a correct electrical supply, often due to the live and neutral wires being swapped or a complete loss of power to the internal components. The most common reason is a failure in the external fuse or a fault within the main circuit board that prevents the system from booting up safely. In some cases, it can be triggered after electrical work has been carried out in the home if the wiring to the boiler was not reconnected in the correct order.
DIY fix possible
Check if your main electrical consumer unit has a tripped circuit breaker.Ensure the boiler's fused spur switch is turned on.Check the fuse inside the boiler's wall switch (spur) and replace if necessary with a 3-amp fuse.
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