Low
S.96 on Vaillant ecoTEC

Your boiler is currently running a brief self-test on its internal water temperature sensors and has temporarily paused heating and hot water to complete this check.

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

Return-sensor check is running, demand (DHW or heating) is blocked

Engineer required

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

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