Low
19 on Viessmann Vitodens 242-F FB2B

Your boiler has lost its connection to the wireless sensor that tells it how cold it is 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

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 and replace the batteries in the wireless outdoor sensor unitEnsure there are no new large metal objects or electronic devices blocking the signal path between the sensor and the boilerPress the reset button on the boiler control panel to see if the connection re-establishes

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