The screw type chiller working principle is as follows:
 
The main feature of a screw chiller is its two helical rotors, one convex and one concave, which interlock to compress refrigerant gas. As the rotors turn, the refrigerant gas is compressed by reducing its volume and transformed into vapor. This vapor then enters the condenser.
 
In the condenser, the high-temperature, high-pressure refrigerant gas exchanges heat with cooling water, transferring the heat to the water. The refrigerant gas then condenses into a high-pressure liquid. The high-pressure liquid refrigerant flows through an expansion valve, which reduces its pressure before entering the evaporator.
 
In the evaporator, the low-pressure liquid refrigerant absorbs the heat from the chilled water, causing the water to evaporate and lower its temperature. The refrigerant gas that vaporizes is then absorbed by the compressor, and the cycle repeats. This continuous process cools the chilled water.