Introduction: Measuring calorimeter figures out the quantity of used heat based on the temperature of water inlet and outlet as well as water that flows through it, which can be applied to the household metering management of heat and cool energy of central heating and cooling system (air conditioners and chilled water system) in cities and towns. Ic card calorimeter mainly consists of flow sensor, temperature sensor, calculator and electric valve. It realizes the measuring and charging control of calorimeters. When there is no energy in the calorimeter, ic card calorimeter will immediately close the valve system. The valve will open automatically as soon as the ic card calorimeter is charged by the user. Functions: 1) measurement and deduction function: when there is flow rate and temperature difference, ic card calorimeter will measure and deduct the actual heat accurately. When there is no any heat, the ic card calorimeter will close the valve system, and meanwhile, the cumulative amount in the ic card calorimeter will be added. 2) display function: varieties of status and data in the ic card calorimeter can be shown circularly through the keys in the lcd. 3) prompting function: error prompt is available when eeprom, clock, and temperature sensor go wrong or when mistakes and problems occur, such as no calibration temperature, abnormal valve and wrong operation etc.. 4) prepaid and charge for heat consumable function: the calorimeter will add the heat purchased to the original and display the current remaining amount after the charged user card has been inserted. Heat will be supplied when the valve is turned on. When there is no heat, the calorimeter will close the valve automatically and cut off the supply of water.