BoilerFaultCodesYour boiler has detected an internal fault or is not receiving a signal to start, and has locked itself out for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler fails to work (checks required: Electrical Plugs PL1 to PL6, External Call for Heat, Boiler Temperature Knob, Gas & Water Connections, Main Supply Voltage).
What causes this fault?
This fault occurs when the boiler's internal computer stops the system because it hasn't received the correct electrical signal to start or has detected a failure in the ignition sequence. The most common reasons include a lack of communication from your wall thermostat, a failure in the electronic control board, or a component like the gas valve not opening to allow the flame to light.
This fault is often seen during the first cold snap of autumn when external thermostats are turned up for the first time and older electronic components struggle to handle the sudden demand.
DIY fix possible
Check that your room thermostat and programmer are turned up and calling for heat.Ensure the gas supply to the property is turned on.Turn the boiler temperature control knob to the 'Off' position, wait 10 seconds, then turn it back to your desired setting to attempt a reset.
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