In his Glossai, we attribute Hesychius to writing that Γέλχανος (Gélchanos) was the name of Zeus on Crete (ὁ Ζεύς, παρὰ Κρησίν) and Ἐλχάνιος (Elchánios), the name of a month in the Cretan city of Knossos. Further we read that Velchania was a Cretan spring festival in honour of the god, mentioned in inscriptions from Lyttos and Gortyn. Understanding the initial gamma of Γέλχανος as a subtle typo for digamma, thus *Ϝέλχανος (Wélchanos), there's a common theme in all of this: a Pre-Greek Cretan god named *Welkʰan. This god is in turn surely related to Etruscan *Velχan which is already accepted by Etruscan specialists to be the unattested source of the Latin name Vulcānus, also of non-Indo-European origin.
If the inherently imprecise comparisons between *Welkʰan and Greek Zeus are based only on a prominent position in the pantheon, and if we already have evidence of an Etruscan solar trinity, the identity of this god and his meaning becomes clear. *Welkʰan appears to be just another name for an aspect of the sun as it passes through the underworld at night. He is then also symbolic of the hope of afterlife and of the sun's re-emergence out of winter's darkness in the spring. This explains the spring festival in his honour and also implies that in Classical Greek times, Pelasgian solar cults and an underlying trinity were still alive and well in Crete, just as in Etruria. Note also the names of Egyptian Amon, the god of the setting sun, and Greek Hades, lord of the underworld, which both fundamentally mean "the Hidden One" or "the Unseen One".
 Perseus Online: ϝέλχανος and Γελχάνος; Flensted-Jensen/Hansen/Nielsen/Rubinstein, Polis & politics: Studies in ancient Greek history (2000), p.88 (see link): "The remaining three month names are Welchanios (I.Cret.IV 3.1; 184.3), Eleusinios (I.Cret.IV 232 + Inv. GO 352; Magnelli ), and Ionios (I.Cret.IV 181.3). Welchanos appears to have been an indigenous Cretan (perhaps Minoan?) god who was later identified with Zeus (Hesych. s.v. Γέλχανος; Willetts  250-251; Capdeville  155-288)." (boldface mine)
 Dietrich, The origins of Greek religion (1974), p.16 (see link).