What does an air conditioner consist of?

A typical air conditioning unit has four main components for the cooling cycle:

1. Evaporator
The liquid refrigerant comes into contact with warm air causing it to evaporate. When the refrigerant evaporates, it absorbs heat from the surrounding air. The warm air is drawn in by a fan and sent back into the room.

2. Compressor
Here the vapour refrigerant (from the evaporator) is 'compressed' to a high pressure so that it can be liquefied more readily (by the condenser) to repeat the cooling process. The compressor also assists by circulating the refrigerant.

3. Condenser
The high-pressure vapour refrigerant (still at high pressure) is relieved of its high temperature via cooling by outdoor air (approx. 30ºC - 35ºC) and is liquefied.

4. Capillary Tube
Here the pressure of the refrigerant (still at high pressure) is lowered by being forced through a narrow tube (capillary tube) resulting in energy loss and a drop in pressure. This sudden lowering of pressure causes a further reduction in temperature. Thus, as the liquid refrigerant flows through the capillary tube, its pressure and temperature are lowered to create a volatile state. Here the vapour refrigerant (from the evaporator) is 'compressed' to a high pressure so that it can be liquefied more readily (by the condenser) to repeat the cooling process. The compressor also assists by circulating the refrigerant.