The Calefactor is a furnace powered by Etherium instead of coal or other fuel items. A Crystal Wrench is needed to link a power source to the Calefactor before it can be used.In order to function, a Calefactor needs at least one type of Etherium to use as fuel: Neutral, Dark, or Light. It takes approximately 180 Etherium to smelt one item with no Mana Foci present, and each Mana Focus added to the Calefactor cuts the Etherium cost by half. So with one Mana Focus; the cost is approximately 90 Etherium, with two, the cost is 45, and with three the cost is 22.5.
Doubling Output Edit
If all three types of Etherium are used simultaneously to fuel the Calefactor, it will double the output of whatever is being smelted. Note that the Calefactor will consume three times as much Etherium while doing this. If only 2 types of Etherium are used to fuel the Calefactor, it will treat them as one fuel source rather than attempting to multiply the smelted item. Note that rarely when using a Calefactor to smelt Arcane Compound into Arcane Ash, if all three types of Etherium are used, instead of doubling the output, the Calefactor will produce 3 Arcane Ash per Arcane Compound rather than 2. It also has a low chance of giving you a Vinteum Dust sometimes when you used it. (At least in earlier versions might still be or might've been patched or intentional) the Vinteum dust that was acquired when melting stuff was enough to keep the process going giving off more Vinteum.