BoilerFaultCodesYour boiler's internal computer has encountered a software or hardware communication error, preventing it from starting up correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: System fault boiler electronics / basic controller
What causes this fault?
This fault occurs when the boiler's internal computer chips fail to communicate or 'handshake' with each other during the start-up sequence. It is usually caused by a physical hardware failure on the main circuit board or a loose connection in the internal wiring. Essentially, the boiler's brain has encountered a critical error that prevents it from safely managing the heating process.
DIY fix possible
Press the 'Reset' button on the boiler control panel onceSwitch the main electrical power to the boiler off and back on again after 30 secondsCheck if the error clears and the boiler restarts its ignition sequence
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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