text: how does a pow-wow water cooler heat water instantly? one quick point - this isn't a stupid question, i know that the main function of a water cooler is to provide cold water. however the water cooler where i work also provides boiling hot water for tea, etc. the hot water comes out of the machine as the same speed as the ice cold water; yet it's actually boiling (with visible steam coming off it). how does the mechanism inside the machine work, to provide this function so quickly and efficiently? i can't find anything useful related to this on wikipedia - so any genuine answers would be very much appreciated; thanks in advance '_' interesting question, the nestle website does not give any answers either :(