Low
19 on Viessmann Vitodens 242-F B2UA

Your boiler has lost its wireless connection to the sensor that measures the temperature outside, which may cause your heating to be less efficient.

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

Communication error with wireless outside temperature sensor

From this model's manual
Verified against the Viessmann Vitodens 242 F B2ua 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

Check the batteries in your outdoor wireless temperature sensor and replace them if necessary.Ensure there are no new large metal objects or electronic devices blocking the signal between the sensor and the boiler.Reset the boiler to see if it automatically re-establishes the wireless link.

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