Basic components of the Refrigeration cycle

Basic components of the refrigeration cycle:

     Components are:

         1)Compressor

         2)Condenser

         3)Evaporator

         4)Expansion valve

Compressor:

• It is the heart of the air conditioning system.
• It is a mechanical device that increases the pressure of a gas by reducing its volume. An air compressor is a specific type of gas compressor.
• The compressor pumps vapour refrigerant at high pressure and temperature into a condenser and receives superheat vapour at low temperature and pressure from the evaporator.  

  Types of compressor:

      a)Reciprocating Compressor

      b)Scroll compressor(Mostly used in VRF)

      c)Screw compressor

      d)Rotary compressor

      e)Centrifugal compressor(used in Chiller Plant).

Condenser:

•  It is a device or unit used to condense a gaseous substance into a liquid state through cooling.
• It is part of the refrigeration system and responsible for heat transfer.
• It receives vapour refrigerant from the compressor at high temperature and pressure and removes heat and pass to the expansion valve.

     Types of condenser:

             a)Aircooled condenser: It is located in outside of the unit, the air-cooled condenser can provide the easiest arrangement. It is easy to install. 

              b)Water-cooled condenser: These condensers are the more efficient type and require regular service and maintenance.

            c)Evaporative Condensor: It can be used inside or outside of a building and under typical conditions, operate at a low condensing temperature.

Evaporator:

• It is the part of the refrigeration system an responsible for heat transfer.
• It receives refrigerant from the capillary tube and this refrigerant in liquid form at low pressure.
•  It changes the phase of refrigerant in to complete vapour form and supplies to the compressor.

     Types of Evaporator:

                a)Bare tube Evaporator

                b)Plate type Evaporator

                c)Finned Evaporator

                d)Shell & Tube Evaporator

Expansion Valve:

•  It controls the refrigerant into the refrigeration cycle.
•  It receives the refrigerant from condenser and it reduces the pressure and passes it to the evaporator.

      Types of Expansion:

            a)Automatic Expansion Valves

            b)Thermostatic

            c)Capillary tube

            d)Float valve

Note: In VRF R410A refrigerant is used.

Refrigerant:

•  It should have Low Boiling point.
•  It should have more latent heat capacity.
•  It should have the property of change in phase in a narrow temperature difference.