High Lockout
E1-72 on Daikin D2CND

Your boiler has detected an internal communication error with its ignition system and has locked itself out for safety.

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

SCOT flame amplifier – reset the boiler

What causes this fault?

This fault occurs when the boiler's main control board loses touch with the electronic system that manages the flame. It is usually caused by a component failure on the circuit board or a faulty sensing electrode that can no longer confirm the burner has lit safely. Because the boiler cannot guarantee the flame is under control, it shuts down instantly to prevent any safety risks.

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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