High Lockout
PCB REPLACED on Ideal Logic Max Heat 2

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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