Low
d.41 on Vaillant ecoTEC plus Aquaplus

This code is simply a diagnostic reading that shows the current temperature of the water returning to your boiler, rather than an error that requires fixing.

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 return temperature

Engineer required

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

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