BoilerFaultCodesYour boiler's computer brain has encountered a serious communication error and cannot tell the system how to operate safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Control system
What causes this fault?
This fault occurs when the boiler's internal computer brain fails to communicate with the sensors or the gas valve that controls the flame. The most common reason is a hardware failure within the electronic control board or a loose connection in the wiring that prevents the system from performing its safety checks.
DIY fix possible
Switch the boiler off at the fused spur power switchWait for 60 secondsSwitch the power back on and press the reset button
Find a Gas Safe engineer
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