A system for heating a medical fluid has at least one first fluid container for storing the fluid, a fluid injector having at least one second fluid container for receiving the fluid from the at least one first fluid container through a fluid path set, at least one heating element positioned in-line with the fluid path set between the at least one first fluid container and the at least one second fluid container of the fluid injector for heating the fluid to a pre-determined temperature as the fluid flows through at least one fluid path element, and a controller for controlling an output of the at least one heating element based on at least one of a property of the at least one heating element and a property of the fluid flowing through the at least one fluid path element.