High Lockout
PCB REPLACED on Ideal Logic Max Heat

Your boiler has recently had its main control board replaced and simply needs to be reactivated to confirm the new part is working.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 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.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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