The portable Flexim FLUXUS F601 Energy is specially designed for temporary heating and cooling Thermal Energy measurement, with all measurements - Flowmeter, Temperature, and BTU computer, contained in one device. Temperature and BTU calculations are done in accordance with EN 1434 Thermal Energy meter standard. The F601 Energy measures the volumetric flow rate non-intrusively via its clamp-on ultrasonic transducers. Simultaneously, temperature probes monitor the temperatures at the supply and return lines of the heating or cooling system. From the temperature difference as well as the measured volume flow rate and the physical media parameters (liquid enthalpy data stored in the meter), the heating or cooling performance is calculated.