Low
d.34 on Vaillant Ecomax Condensing 600/800 series

Your boiler is simply reporting the current speed at which the internal air fan is spinning, rather than indicating a fault.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Current fan speed value

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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