High Lockout
EA on Ideal Maximiser SE

Your boiler’s internal computer has developed a fault and can no longer communicate with the rest of the system, causing it to stop 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

Defective control panel.

What causes this fault?

This fault occurs when the boiler's internal computer brain suffers a component failure, preventing it from sending or receiving signals to the burner and pumps. The most common reason is electrical degradation of the circuitry over time, or a loose connection between the display panel and the main control board.

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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