What is the condensation pressure control method for refrigeration chiller?

　　What is the condensation pressure control method for refrigeration chiller?

　　The basic idea of regulating and controlling the condensation pressure from the refrigerant side is to accumulate liquid in the refrigerant section of the air-cooled chiller condenser, occupying a portion of the effective heat exchange area, reducing the heat removal capacity, in order to maintain the condensation pressure at a high level and maintain the normal operation of the air-cooled chiller, especially in low-temperature environmental conditions.

　　This is a cheap and effective regulation method that uses a combination of high-pressure and differential pressure control valves to ensure sufficient condensation pressure during equipment operation.

　　The high-pressure regulating valve is installed on the pipe liquid at the outlet of the condenser, and the differential pressure regulating valve is installed on the side channel between the high-pressure exhaust and the reservoir. Utilize the coordination between the high-pressure regulating valve and the differential pressure regulating valve for regulation. The high-pressure regulating valve is a proportional regulating valve that has always been controlled by the pressure in front of the valve.

　　Its opening is proportional to the deviation of the condensation pressure relative to the opening pressure. When it falls below the set value, the valve closes. When the set value is reached, the valve begins to open. Under normal circumstances, the valve is fully open. Differential pressure regulating valve is a proportional regulating valve controlled by the pressure difference in front of the valve, which cannot be opened when the pressure difference is large.

　　A small pressure difference means that the valve opening decreases. When the pressure difference is lower than the set pressure difference for opening the valve, the valve is completely closed. The magnitude of this pressure difference depends on the degree of throttling of the high-pressure valve, and the higher the throttling degree, the greater the pressure difference.

　　In low temperature environments, the condensing pressure of the chiller is too low, the throttle valve lacks sufficient hydraulic power, and the high-pressure liquid pipe is constantly affected by heating factors, which will reduce the capacity of the throttle valve. Therefore, it is imperative to control the condensing pressure of the low-temperature chiller year-round.

　　The pressure of the condenser can be controlled by adjusting its heat exchange capacity. When the heat transfer of the condenser increases, the gas discharged by the compressor (vortex piston) is fully condensed, and the condensation pressure gradually decreases; If the heat transfer performance of the condenser is weakened, the condensing pressure will continue to rise.