Basic Of Air Conditioning

Basic of Air Conditioning Prepared by: Amr Mohammed

1Definition Air Condition :is absorber or removal of heat from indoor air for thermal comfort by using chemistry medium

Evaporative air coolers, sometimes called "swamp air conditioners", do not have a compressor or condenser. Liquid water is evaporated on the cooling fins, releasing the vapour into the cooled area2

Human Comfort Human Comfort or Thermal Comfort is defined as the state of mind in humans that expresses satisfaction with the surrounding environment3Units1 btu (British Thermal Unit) equivalent to burn one match stick or to raise 1 pound of water 1 deg.FTR (Ton of Refrigerant) was defined as the energy removal rate that will freeze one short ton of water at 0 C (32 F) in one day1TR = 12,000 btu/hr1TR = 3.517 Kw1TR = 9,000 btu/hr1TR = 3,024 Kcal/hr

4Basic Component of Air Condition

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Function of Components Evaporator (Indoor unit) to absorb or remove the heat from indoor.

6Function of Component Cont Compressor defined as the heart of air conditioning system. The functions of compressor are to compress the gas and raise the temperature above the ambient in order to reject the heat

7Function of Component Cont Condenser (Outdoor Unit) is to reject heat from system to the outside

8Function of Component Cont Refrigerant is a compound used in a heat or cool cycle that undergoes a phase change from a gas to a liquid and back.

9ContinueBoiling points can be increased or decreased by raising or lowering the pressure on the liquidIncreased pressure=increased boiling point

Decreased pressure=decreased boiling point

On top of Mount Everest, at 8,848m (29,029 ft) elevation, the pressure is about (26.000kPa ) and the boiling point of water is 69C (156.2F ). The boiling point decreases 1 C every 285 m of elevation, or 1 F every 500 ft.

Boiling Point = 242 Deg F or 116.7 Deg.CAtmospheric Pressure14.679 Psi or 101KPa or 0 m SLBoiling Point = 212 Deg. F or 100 Deg.C10 psi10ContinueRefrigerants are divided to Natural Refrigerant such as (air, CO2, NH3, water, etc)One Compound of chemical Refrigerant such as (R-22, R-12, etc) Blends are divide to

Azeotropic blends is a mixture of two or more liquids in such a ratio that its composition cannot be changed by simple distillation.R-500 series are example of it.

Zeotropic blends is the composition of the vapor and the liquid phase at the vapor-liquid equilibrium state are never the same. R-400 series are example of it.11

Shall I know It?s12Example of Blend

R-407C is a zeotropic hydrofluorocarbon blend of R-32, R-125, and R-134a.R-134 a boiling point at (26.3 C) with 40% wtR-125 a boiling point at (48.5 C) with 40% wtR-32 a boiling point at (52.0 C) with 20% wtWhich one evaporate the first 13Function of Component Cont Capillary Tube or Thermostatic Expansion Valve (TXV) works to reduce the high pressure to low pressure.

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Basic Concept about Re.CycleCompressor can handle the gas only

Gas enters evaporator as liquid and exit as vapour

Gas enters condenser as vapour and exit as liquid 123415

P-H Diagram 16P-H Diagram

17P-H Diagram

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What about big Unit?In fact all has the same concepts and principles of small unitsWith few deference: Indoor unit change to AHU or FCUOutdoor condenser still same if use air cooled and if water will be cooling tower.

Condenser

Evaporator

19Do not be Confused ??

20Q &A21All Thank to Allah

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