High Lockout
EL on Ideal Maximiser SE

Your boiler’s main computer screen or internal control board has developed a fault and is no longer communicating correctly 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 data link between the internal computer and the front display panel is broken, often caused by a component failure on the circuit board itself. It is usually the result of age-related wear or a power surge that has damaged the delicate electronics responsible for sending signals through the boiler.

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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