Low
d.34 on Vaillant ecoTEC plus Aquaplus

Your boiler is simply displaying the current operating speed of its internal fan, which is a normal piece of technical information rather than a fault code.

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.

Technical description

Actual value of the rotary speed of the fan

Engineer required

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

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Related fault codes

d.00View →d.33View →

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