Low
d.51 on Vaillant ecoTEC Plus 615

Your boiler is currently recalibrating its internal fan settings and is not reporting a failure; it is performing a routine adjustment rather than displaying an active heating 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.

Technical description

Correction of the maximum fan speed: -2500 to 0 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

F.32View →F.61View →

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