Low
d.39 on Vaillant ecoTEC Plus 832

This code is simply an information display showing the current temperature of the water in your solar heating system, rather than indicating 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

Water temperature in the solar circuit: Current value

Engineer required

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

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