High Lockout
7H on Ideal Maximiser SE

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

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 suffer a hardware failure or a communication breakdown between the electrical components. The most common reason is natural wear and tear of the delicate electronic circuits over time, or damage caused by an unexpected electrical power surge.

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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