A modular fluid unit for cooling heat sources located on a rack, the modular fluid unit comprising: a heat exchanger in fluid communication a pump; and wherein the modular fluid unit is mountable within the rack and is configurable to be in fluid communication with a cold plate return manifold, a cold plate supply manifold, and an end-user fluid supply. A method for cooling electronic components in a rack, the method comprising: circulating a first liquid from a cold plate to one of a plurality of heat exchangers mounted within the rack; circulating a second liquid from a second liquid supply to the one of a plurality of heat exchangers; and transferring heat from the first liquid to the second liquid at the one of a plurality of heat exchangers.