Low
d.20 on Vaillant ecoTEC plus System

This code indicates that your boiler is currently working within its normal temperature settings for your hot water and does not represent a system 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

Maximum hot water set target temperature: 50 to 60 ℃

Engineer required

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

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