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F.084

The temperature difference between the flow and return temperature sensors returns implausible values.

Vaillant ecoTEC Plus Combi

Possible cause
Flow temperature sensor installed incorrectly
Measure
Check whether the flow temperature sensor has been installed correctly.
Possible cause
Return temperature sensor installed incorrectly
Measure
Check whether the return temperature sensor has been installed correctly.
Possible cause
Flow and return temperature sensors inverted
Measure
Check whether the flow and return temperature sensor has been installed correctly.
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