Low
d.33 on Vaillant ecoTEC plus System

Your boiler is currently monitoring the speed of its internal air intake fan to ensure it is operating at the correct level for safe combustion.

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

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

Engineer required

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

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Related fault codes

F.32View →F.61View →F.62View →

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