A:Answer If you have plenty of space to work above the unit (at lease 1-ft), and you fill it from the right container (not the carafe, maybe a narrower pitcher) you can do so pretty easily without spilling water. If, on the other hand, you have limited space it can be difficult to reach the back right corner of the unit where you need to fill. Also, if you use the carafe to fill it seems to spill a small percentage sometimes due to the angle at which you are forced to hold the carafe.