Vaillant GmbH

Any device whose MAC address begins with 84:C3:E8 has a network interface built by Vaillant GmbH. This prefix (the OUI, or Organizationally Unique Identifier) is assigned by the IEEE and is the first three octets of the address.

OUI prefix

84:C3:E8

Organization

Vaillant GmbH

Address

Berghauser Straße 40 Remscheid NRW DE D-42859

Source

IEEE OUI registry

Have a full MAC address? Look it up— we'll also tell you if it's a randomized (private) address rather than a real manufacturer prefix.