Low
d.34 on Vaillant ecoTEC Plus 938

This code is simply showing you the current speed of your boiler's internal cooling fan and is not a warning of a fault.

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

Value for the fan speed: 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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