High Lockout
11-64 on Daikin D2CND

Your boiler is having trouble lighting the gas to start the heating process and may need to be restarted.

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

Ignition error – possible fault with valve on the gas line due to it being open. Try resetting the boiler after the third unsuccessful ignition

What causes this fault?

This fault occurs when the boiler's control system detects that the gas valve is open but it cannot successfully establish or sense a flame. The most common reasons are a physical failure of the gas valve mechanism, worn-out ignition electrodes that can no longer produce a strong spark, or a degraded spark cable that is leaking electricity before it reaches the burner.

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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