Fluid temperature control system

Described herein is a system for heating and/or cooling a fluid that includes a temperature forcing device having a bottom plate and a top plate hingedly coupled to the bottom plate. At least one of the bottom plate and the top plate has a recess or other area for receiving at least one flexible fluid holder (e.g., a polymer bag). The bottom plate and/or top plate also has at least one protrusion and/or recession in its interior wall(s) such that a fluid passageway in the flexible fluid holder is defined when the fluid holder is placed between the top and bottom plates, and the plates are closed together. The fluid holder then has a fluid inlet for receiving the fluid to be heated and/or cooled and a fluid outlet for delivering the fluid. The fluid, upon being heated and/or cooled by the temperature forcing device, may then be delivered to a patient or may be delivered to another system component, e.g., for additional heating/cooling.