BoilerFaultCodesYour boiler has recently had its main control board replaced and simply needs to be reactivated to confirm the new part is working.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Restart boiler by pressing RESTART after a board change.
What causes this fault?
This code appears because the boiler's internal computer brain, the Printed Circuit Board, has been swapped for a new one. The boiler enters a temporary hold state to ensure the new component is officially recognised and synchronised with the rest of the unit. It is a security and safety step to confirm the repair is complete and the system is ready to fire up again.
DIY fix possible
Locate the display panel on the front of the boilerPress the button labelled RESTARTWait for the boiler to complete its start-up sequence
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A boiler cover plan would cover faults like PCB REPLACED — no call-out fees, no surprises.
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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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