Low
S.0 on Vaillant ecoTEC plus System

Your boiler is perfectly healthy and is simply waiting for a signal from your thermostat or timer to start heating your home or water.

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

Heating mode: No requirement

Engineer required

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

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