how to work refrigeration cycle work

AIR TEMPERATURE 

Temperature and Temperature Scales 

The temperature of a substance is a measure of how hot or cold it is. Two systems are said to have equal temperatures only if there is no change in any of their observable thermal characteristics when they are brought into contact with each other. Various temperature scales commonly used to measure the temperature of various substances are illustrated in Fig. 2.2. In conventional inch-pound (I-P) units, at a standard atmospheric pressure of 14.697 psia (101,325 Pa), the Fahrenheit scale has a freezing point of 32°F (0°C) at the ice point, and a boiling point of 212°F (100°C). For the triple point with a pressure of 0.08864 psia (611.2 Pa), the magnitude on the Fahrenheit scale is 32.018°F (0.01°C). There are 180 divisions, or degrees, between the boiling and freezing points in the Fahrenheit scale. In the International System of Units (SI units), the Celsius or Centigrade scale has a freezing point of 0°C and a boiling point of 100°C. There are 

100 divisions between these points. The triple point is at 0.01°C. The conversion from Celsius scale to Fahrenheit scale is as follows:

°F 1.8(°C) + 32