The 800X pressure difference balance valve is a kind of valve intended for use between the water supply part and the return water part of an air conditioning system to balance the pressure difference. This valve can increase the utilization factor of a system, maintain the pressure difference at a precise constant value, and maximally reduce the system noise and avoid damages caused to the equipment because of an excessive pressure difference. The 800X pressure difference balance valve excels over other balance valves in the fact that it does not have an actuating mechanism, depends entirely on its own pressure difference to realize the function of balancing the system, and saves energy and the space required for installation. It can therefore be regarded as a kind of intelligent valve.