A system (20) including a heater/cooler module (22) to heat/cool a first fluid in a primary circuit (28), a heat transfer fluid circuit (24) to provide a second fluid to a target device (38) to heat/cool the target device (38), and a heat exchanger (26) including at least part of the primary circuit (28) and at least part of a secondary circuit (36) through which the second fluid flows to facilitate heat transfer between the first fluid and the second fluid. The primary circuit (28) and the secondary circuit (36) are separate circuits and the first fluid and the second fluid remain separated in the system. Also, the system is modular, such that the elements can be stacked to increase heating/cooling capability and/or to increase the number of heating/cooling channels, and the system is compatible with portable applications, such as ambulance, aircraft, and helicopter applications, and with battery operation and/or the use of uninterruptible power supplies.
