High Lockout
4.16 on Ideal Logic Max Combi

Your boiler has lost all power or the control screen has failed, meaning the system will not turn on or provide heat.

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

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What causes this fault?

This fault occurs when the boiler's internal computer is no longer receiving electricity or has suffered a critical hardware failure. The most common reason is a blown fuse on the main circuit board caused by a power surge, though it can also happen if moisture has damaged the electronic components. Without a functioning brain to coordinate the sensors and valves, the boiler stays completely inactive for safety.

This issue is slightly more common during the autumn and winter months when increased electrical demand on the national grid leads to power fluctuations or surges that can trip the boiler's internal electronics.

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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