YORK 025-40900-002 Thermostatic Expansion Valve

025-40900-002 is the original part number of York (a brand under Johnson Controls). The standard description is "Thermostatic Expansion Valve (TXV)", which belongs to the Valves category. For European and American component manufacturers, the product name is directly written as "VALVE TXV".
Working principle and function: The thermostatic expansion valve is a mechanical throttling device, installed at the inlet of the liquid pipe of the evaporator. It is composed of a temperature sensing bulb, a capillary tube, a diaphragm and a spring. The temperature sensing bulb is attached to the suction pipe at the evaporator outlet, sensing the suction superheat and driving the diaphragm to move, causing the valve needle to shift automatically, thereby regulating the refrigerant flow entering the evaporator, thus maintaining a stable superheat at the evaporator outlet. This can avoid the waste of heat exchange area and the decline in energy efficiency caused by insufficient liquid supply, and also prevent the liquid supply from being excessive, causing compressor liquid strike (backflow). Compared with electronic expansion valves, it does not require power supply and controller, has a simple structure and high reliability, and is a regular configuration for small and medium-sized commercial and household air conditioners and refrigeration units.