Fuser assemblies for fusing toner on support sheets, electrophotographic apparatuses, and methods of fusing toner on support sheets are disclosed. The fuser assembly includes a fuser belt; a thermally-insulated enclosure surrounding at least a portion of the fuser belt; a conveyor for conveying the support sheet to a nip at which the fuser belt contacts the support sheet and the toner is fused onto the support sheet; a pre-heater; and a heat transfer system for transferring heat from inside of the enclosure to the pre-heater, the pre-heater using the heat to pre-heat the support sheet before the support sheet is conveyed to the nip.