Tap water temperature changes as different season, its temp. is higher in summer, so solvent recovery efficiency is low, and tap water will make condenser change color and scale formation.
You could choice the below two lab solutions:
1) The best solution: equip appropriate low temperature cooling circulating pump, when you choice, please pay attention to "refrigerating capacity", "lowest temperature", "circulating joint", "circulation capacity" and "circulating pressure", TOPTION supply low temperature equipment professional for rotary evaporator.
2) For laboratory rotary evaporator, cold trap could be cooling by ice.