Adjustable 435 Psi Differential Pressure Switches 174 Psi 246 psi Description QYD Series DPS Adjustable Differential Pressure Switches for Air Conditioning QYD series differential pressure switch is designed to prove flow through pumps. It can be used in fluorinated refrigerant, also in air and liquid (-20 to 120°C), renovated SPDT micro-switch ensure the reliable switch function and flexible mounting bracket suits various kinds of application. Model Specification Model