BoilerFaultCodesYour boiler's internal computer has become confused during its startup sequence and has stopped working 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: Software Sequence Error
What causes this fault?
This fault occurs when the boiler's internal control board fails to follow its programmed safety checks in the correct order during startup. It is usually caused by an electrical glitch or a failing component on the circuit board that prevents the system from confirming it is safe to ignite. In some cases, loose or damaged wiring between the sensors and the main computer can also trigger this confusion.
DIY fix possible
Locate the reset button on the control panelPress and hold the reset button for 5 secondsWait for the boiler to attempt to restartIf the lights return, turn the power off at the wall spur for 30 seconds and then back on
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