High Lockout
F.85 on Glow-worm Energy System

Your boiler has shut down because its internal electrical components have become too hot and need to cool down.

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

Electronics temperature too high

What causes this fault?

This fault occurs when the boiler's internal sensors detect that the main control board has reached a dangerously high temperature. It is usually caused by excessive heat building up inside the boiler casing, often due to a component failure or a loose electrical connection causing a short. To prevent permanent damage to the electronics, the system shuts down automatically to allow everything to cool over time.

This fault can be more common during heatwaves or in very small, unventilated cupboards where the ambient air temperature prevents the boiler from cooling itself effectively.

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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