High Lockout
EH on Ideal Maximiser SE

Your boiler’s main control screen or internal computer has developed a fault and can no longer communicate with the rest of the system.

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 link between the boiler's main brain and its display screen is broken, often due to an internal electrical component failure. It is usually caused by age-related wear on the circuit board or a loose connection that prevents the system from sending start-up instructions. Because the control panel can no longer 'talk' to the boiler, the unit shuts down safely to prevent erratic behavior.

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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