Low
F.13 on Viessmann Vitodens 200-W B2HF System

Your boiler has lost its connection to the sensor that measures the temperature outside, meaning it may not know how hard it needs to work to heat your home.

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 200 W B2hf System installation & service manual, page 87.
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

Check the outside sensor for any obvious signs of physical damage or loose casingInspect the visible cable running from the sensor for any breaks or animal damageTry resetting the boiler to see if the fault clears (it may be a temporary software glitch)

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