Low
N.100 on Vaillant ecoTEC Plus 832

Your boiler has lost the connection to the small sensor located outside your home that tells it how cold it is so it can adjust your heating automatically.

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

Outdoor temperature sensor not connected. The signal for the outdoor temperature sensor has been interrupted.

From this model's manual
Verified against the Vaillant Ecotec Plus installation & service manual, page 94.
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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