High Lockout
uP on Ideal Logic Combi C24 C30 C35

Your boiler is currently stuck in its startup or programming sequence and is not yet ready to provide heat or hot water.

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

PCB Power up / Programming Mode

What causes this fault?

This fault occurs when the boiler's main internal computer loses its configuration or gets stuck during its initial boot sequence. The most common reason is a power surge or a failing printed circuit board that can no longer hold its basic programming instructions.

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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Related fault codes

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