Low
d.50 on Vaillant ecoTEC plus System

Your boiler is currently running a calibration routine to adjust its internal air supply settings to meet efficiency standards.

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

Correction of the minimum fan speed: 0 to 3000 rpm. Fan speed=Display value x 10

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.51View →

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