The ppt contains detailed study of all the components used in refrigeration and air conditioning system with neat sketches and description. It is well formed as per the syllabus of GTU

1. Refrigeration System
Components
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Faculty Name: Prof. Ajaypalsinh G. Barad
Branch: Mechanical
Semester: 6th
Name of Subject: Refrigeration and Air Conditioning

2. Outline
• Introduction
• Compressor
• Condenser
• Expansion Device
• Evaporators
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3. 3

4. Compressors:
• It removes low temperature and low pressure
refrigerant vapours from the cooling coil through the
suction line.
• It compresses these refrigerant vapours by increasing
the pressure and temperature resulting in an increase
of boiling point of the refrigerant,
• It discharges the refrigerant vapours of high
temperature and pressure to condenser through
discharge line.
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5. Compressors:
There are mainly three types of compressors in use:
Reciprocating compressor,
Rotary compressor,
Centrifugal compressor
• Reciprocating and rotary compressors are more commonly
used for small capacities but for lower evaporator
temperatures.
• Centrifugal compressors are essentially large discharge
capacity compressors. These are preferred for higher
evaporator temperatures applications like, water chillers
and air conditioners. They offer high efficiency but are
expensive.
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6. Reciprocating Compressor:
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7. Reciprocating Compressor:
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8. Rotary Compressor:
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9. Rotary Compressor:
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10. Rotary Compressor:
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11. Rotary Compressor:
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12. Rotary Compressor:
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13. Centrifugal Compressor:
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14. Screw Compressor:
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15. Scroll Compressor:
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16. Scroll Compressor:
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17. Hermitecally Sealed Compressor:
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18. Condensers:
• A condenser is a heat exchanger which removes heat
of the hot vapor refrigerant discharged from the
compressor.
• The condenser are classified into the following three
groups:
(1) Air-cooled condensers
(2) Water-cooled condensers, and
(3) Evaporative condensers.
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19. Air-cooled condensers
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20. Water-cooled condensers
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21. Water-cooled condensers
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22. Water-cooled condensers
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23. Evaporative condensers
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24. Expansion devices:
• Following are the main types of expansion devices
used in industrial and commercial refrigeration and air
conditioning system.
1.Capillary tube
2.Hand-operated expansion valve
3.Automatic or constant pressure expansion valve
4.Thermostatic expansion valve
5.Float valve
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25. Expansion devices:
• Capillary tube
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26. Expansion devices:
• Capillary tube
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27. Expansion devices:
• Capillary tube
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28. Expansion devices:
• Capillary tube
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29. Expansion devices:
Capillary tube
• The pressure drops due to the frictional resistance
• For a given state of the refrigerant, the pressure drop is directly
proportional to the length and inversely proportional to the bore
diameter of the tube
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30. Expansion devices:
• Hand operated expansion valve
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31. Expansion devices:
• Automatic Expansion Valve
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32. Expansion devices:
• Thermostatic Expansion Valve
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33. Evaporators:
• The function of an evaporator is to absorb heat from
the surrounding location or medium which is to be
cooled by means of a refrigerant.
• The evaporators may be classified as follows:
According to operating conditions:
(i) Flooded type evaporators;
(ii) Dry or direct expansion type evaporators.
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34. Evaporators:
According to type of construction:
• Bare tube coil evaporator,
• Finned tube evaporator,
• Plate evaporator,
• Shell and tube evaporator,
• Shell and coil evaporator,
• Tube-in-tube evaporator,
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35. Evaporators:
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36. Evaporators:
• Capillary tube
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37. Evaporators:
• Bare tube coil evaporator
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38. Evaporators:
• Finned tube evaporator
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39. Evaporators:
• Plate Evaporator
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40. Evaporators:
• Shell and tube evaporator
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41. Evaporators:
• Shell and Coil
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42. Evaporators:
• Tube in Tube
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43. Refrigeration piping:
Selection of piping and fittings on the basis of
• Frictional resistance offered by pipe wall to flow of fluid,
• Velocity of flow.,
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44. Refrigeration piping:
The design and operation of refrigerant piping system are as
follows:
• Ensure proper feed of refrigerant to the evaporators.
• Refrigerant line be so designed that pressure drop is not
excessive.
• Excessive amounts of lubricating oil may not be trapped in
any part of the system.
• It should protect the compressor from the loss of refrigerant
and lubricating oil.
• It should prevent liquid refrigerant from entering the
compressor during operating and idle time.
• It should maintain dry and clean system.
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45. Refrigeration Accessories :
Oil separator:
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46. Refrigeration Accessories :
Sight glass:
The sight glass is used as for,
• Moisture indicator.
• Liquid indicator.
• Liquid level indicator.
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47. Refrigeration Accessories :
Driers :
• Moisture in refrigeration systems is factor in the formation
of acids, sludge and corrosion.
• Drier is used to remove moisture from the system.
• It is placed in liquid line just before a strainer.
• It has silica gel in it to absorb the moisture either left over
in the system after charging or developed over a period due
to chemical action on oil.
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48. Refrigeration Accessories :
Filters :
• The filters act to strain out any particles that may be in
the system.
• Any particles can plug capillary tubes and thermostatic
expansion valve screens.
• The filter is placed at the inlet to the expansion device.
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49. Refrigeration Accessories :
Receiver :
• A receiver is a storage area for refrigerant.
• The liquid from condenser goes by gravity to a receiver.
• It is used to take care of load variation.
• It also help the condenser to drain refrigerant freely.
• The outlet tube of the receiver ensures that only liquid
goes to expansion device.
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50. Refrigeration Controls :
The controls used to cycle the refrigerating system on or
off are of two principle type,
• Temperature actuated,
• Pressure actuated.
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51. Refrigeration Controls :
Temperature actuated control:
• A temperature actuated control is also known as
thermostats.
• The temperature actuated controls are:
– Bulb type temperature sensing element,
– Bimetal type temperature sensing element.
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52. Refrigeration Controls :
Pressure actuated controls:
• They are used to control the pressure of the refrigerant in
the system. It is used as safety controls.
• Low pressure cutout
• High pressure cutout
• Oil failure cutout
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53. Thermal insulation:
• The materials having extremely low thermal conductivities
are called insulating materials.
• Desired properties of an ideal insulating material
– Thermal conductivity
– Permanence
– Strength
– Water-repellent
– Fire-proof
– Light weight
– Odorless
– Low-cost
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54. Classification of insulating materials:
• Flake insulation
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55. Classification of insulating materials:
• Fibrous insulation
– Organic or inorganic and may or may not be bonded.
– Glass or Rockwool are the most common materials
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56. Classification of insulating materials:
• Granular insulation
– Composed of small nodules that contain voids
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57. Classification of insulating materials:
• Cellular insulation
– Composed of small individual cells produced from glass,
rubber or plastic
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58. Classification of insulating materials:
• Reflective insulation
– Composed of parallel thin sheets of foil having high thermal
reflectance
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