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F.49

Fault: eBUS

Vaillant ecoTEC Pro 28 Combi

Possible cause
Undervoltage on the eBUS
Measure
Check: eBUS (overload, two power supplies with different polarities, short circuit).
This code also applies to:
ecoTEC Pro 24 CombiecoTEC Pro 30 Combi
Source: Manufacturer manual (PDF)
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