High Lockout
f028 on Intergas Xtreme 24

Your boiler's computer system is having trouble completing a reset or start-up sequence and needs a technician to check it.

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

Reset error.

What causes this fault?

This fault happens when the boiler's internal computer fails to properly complete its reset process or becomes stuck during a startup sequence. It is often caused by a communication failure between the electronic control board and the internal wiring, or a hardware defect within the board itself. Because the boiler can no longer verify its safety checks, it stops running to prevent any 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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