Low
S.096 on Vaillant ecoTEC plus Combi

Your boiler is currently running a set of automatic internal diagnostic checks and has temporarily paused heating and hot water to ensure everything is working correctly.

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.

What the manual says

Manufacturer manual

The self-test for the return temperature sensor is active. The heat demands are blocked.

From this model's manual
Verified against the Vaillant Ecotec Plus installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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