Low
13 on Viessmann Vitodens 100-W B1GA

Your boiler has lost its connection to the outdoor weather sensor, which means it may not know how hard it needs to work to heat your home efficiently.

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

Lead break, outside temperature sensor

From this model's manual
Verified against the Viessmann Vitodens 100 W B1ga installation & service manual, page 53.
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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