A temperature controlled fluid therapy system includes a reservoir for containing hot or cold fluid, a pump with a submersible motor disposed within the reservoir, a watertight blanket for containing the hot or cold fluid, and output and intake conduits for circulating the fluid between the reservoir and the blanket. The system includes a first temperature sensor disposed within the reservoir for measuring the temperature of the fluid in the reservoir, and a second temperature sensor disposed adjacent the blanket for measuring the temperature of the fluid in the blanket. A power supply provides power to the pump motor. A controller controls the power provided to the motor based upon the first and second temperature signals, thereby controlling the fluid flow rate through the blanket and hence the temperature of the fluid in the blanket. When the temperature of the fluid in the reservoir is within a hot temperature range, such as 90° F. to 120° F., the controller maintains the temperature of the fluid in the blanket within the hot temperature range. When the temperature of the fluid in the reservoir is within a cold temperature range, such as 45° F. to 65° F., the controller maintains the temperature of the fluid in the blanket within the cold temperature range.