There is a hotel of the same name (Hotel Centro Naval) nearby at Cordoba 622. A reviewer got his lines crossed I think. Though I haven't tested it personally, being always with a naval associate, the Centro Naval website is pretty clear on the subject of public attendance - tripadviser maybe not so much.
Visiting the Centro Naval website again, I noticed and as Silvie noted:
Visitas guiadas a la Sede Central del Centro Naval. Una extraordinaria experiencia en uno de los edificios más representativos de la ciudad de Buenos Aires. Todos los sábados, 12 hs. y 16 hs. A cargo de guías de la Fundación Arq. Ing. Francisco Salamone, preparados por el historiador Eduardo Lazzari.
CON RESERVA PREVIA llamando al 4382-9989. Cupo de 30 personas.
http://www.centronaval.org.ar/sedes/sede-central.html