Chillers use either a vapor-compression or absorption refrigerant cycle to cool a fluid for heat transfer. Both chiller types rely on three basic principles.
First – When a liquid is heated it vaporizes into a gas, and when a gas is cooled it condenses into a liquid
Second – Lowering the pressure above a liquid reduces its boiling point and increasing the pressure raises it
Third – Heat always flows from hot to cold.
Basic Cooling Cycle
The basic cooling cycle is the same for both vapor-compression and absorption chillers. Both systems utilize a liquid refrigerant that changes phase to a gas within an evaporator which absorbs heat from the water to be cooled.The refrigerant gas is then compressed to a higher pressure by a compressor or a generator, converted back into a liquid by rejecting heat through a condenser and then expanded to a low- pressure mixture of liquid and vapor that goes back to the evaporator section. The cycle is repeatedi