High Lockout
E08 on Keston C36

Your boiler is having trouble managing the flame and electrical signals, which is preventing it from heating your home safely.

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

Flame circuit error - possible control box fault..

What causes this fault?

This fault occurs when the boiler's internal computer is unable to correctly process the electrical signals required to monitor the flame. It is usually caused by a communication failure between the sensing hardware and the main control board, meaning the boiler shuts down because it cannot verify that it is burning gas safely. In many cases, this is due to moisture on the electronics or a component failure within the circuit board itself.

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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