What causes reciprocating compressor valves to operate?

Reciprocating compressor valves operate primarily due to cylinder pressure differences. As the piston moves within the cylinder, it creates varying pressure conditions. When the pressure inside the cylinder drops below the pressure in the suction line, the suction valve opens, allowing refrigerant to flow into the cylinder. Conversely, when the piston moves back down, compressing the refrigerant, the pressure inside the cylinder becomes higher than that of the discharge line, causing the discharge valve to open and allowing the refrigerant to exit the cylinder. This cycle of creating pressure differentials is essential for the valves to function correctly, enabling the compressor to draw in and expel refrigerant effectively, thereby facilitating the refrigeration cycle.