3.4.Expansion devices

Unit 3 - Parts of refrigeration systems

3.4.Expansion devices
The expansion device is an important device that divides the high pressure side of a refrigerating system. It is connected between the receiver and the evaporator. The expansion device performs the following functions:
  • It reduces the high pressure liquid refrigerant to low pressure liquid refrigerant before being fed to the evaporator.
  • It maintains the desired pressure difference between the high and low pressure sides of the system, so that the liquid refrigerant vaporizes at the designed pressure in the evaporator.
  • It controls the flow of refrigerant according to the load on the evaporator.
Types of metering device:
  • There are six main types of refrigerant control devices
  • Hand operated expansion valve
  • Low and high pressure side float valve
  • Automatic expansion valve
  • Thermostatic expansion valve
  • Capillary tube.
Last modified: Monday, 22 August 2011, 10:21 AM