Low
10 on Viessmann Vitodens 100-W B1HC-19

Your boiler has detected an electrical fault with the external weather sensor on the outside of your property, meaning it may not adjust its temperature correctly based on the weather outside.

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

Continuous operation, Short circuit, outside temperature sensor, Check the outside temperature sensor and lead (see page 52).

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 100 W B1hc B1kc 19 35 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.

DIY fix possible

Locate the outside temperature sensor on the exterior wall of your home.Check the wiring leading to the sensor for any visible damage, cuts, or loose connections.Ensure no loose debris, moisture, or pests have interfered with the sensor housing.

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Related fault codes

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All 29 fault codes on the Vitodens 100-W B1HC-19

Seeing a different code? Every code this model can display, in one place.

0C5A1830385051525859A3A9b0b7b8E3E5F0F1F2F3F4F8F9FAFCFdFF

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