High Lockout
EC on Ideal Maximiser SE

Your boiler's internal computer has developed a fault and is unable to manage the heating system correctly.

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 chips or electrical circuits suffer a hardware failure, meaning the different components can no longer talk to each other. The most common reason is general wear and tear of the electronic capacitors over time, or an electrical surge that has damaged the delicate tracking on the circuit 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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