Low
d.33 on Vaillant ecoTEC Plus 630

Your boiler is displaying the current operating speed of the fan, which is a normal status message rather than a breakdown.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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.

What the manual says

Manufacturer manual

Fan speed target value: Current value in rpm. Fan speed=Display value x 100

From this model's manual
Verified against the Vaillant Ecotec Plus 615 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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F.32View →F.61View →

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