BoilerFaultCodes.com
PCB REPLACED High Lockout

Your boiler has recently had its main circuit board changed and simply needs a quick reset to finish the setup process.

Call an engineer soon

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

What causes this fault?

This message appears because the boiler’s main control board has been replaced and requires a final confirmation to synchronise with the rest of the components. It is a built-in safety step to ensure the new part is recognised correctly before the boiler begins its normal heating cycle. Once you press the restart button, the system will clear this notification and resume operation.

Typical repair cost £0 (including labour)

DIY fix possible

Locate the 'RESTART' button on the front control panelPress the button firmly onceWait for the boiler to complete its start-up sequence

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Protect yourself from future repair bills

A boiler cover plan would cover faults like PCB REPLACED — no call-out fees, no surprises.

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