Molecules, heat, and temperature
When we think of the heat we tend to think, temperatures, though not very measure the heat capacity. To understand this, we should carefully look at it. In the discussion that follows, we will have in mind, R-22, a total refrigerant.
In this example, we see that the smallest particles with all the qualities, R-22 is a molecule. This is true of any substance, whether gas, liquid or solid. The figure shows a few molecules R-22, as a liquid at -20F. At this temperature, the molecules vibrate at a certain speed or speed, they are at a certain distance from each other, and they are arranged in a special way. Density is a measure of how densely Packed the molecule. It is measured by the weight of the unit of space or volume, for example, in pounds per cubic foot. Temperature Indicates the Average Velocity of the Molecules of the Substance.
As the temperature of the fluid increases, absorbing heat from -20F 40F, molecules vibrate more quickly and move a little farther apart.
The density of the liquid refrigerant has changed very little. Temperature indicates the average velocity of the molecules of the substance. Any pure substance can change its state. Solids may change for liquids and liquids can be changed in pairs and back. These state changes occur when a certain combination of temperature and pressure for each substance.
Refrigerant R-22 changes from liquid to vapor at 40F and a pressure of 69 psi, for example. Therefore, as we still warm R-22, it will eventually turn into steam or gas. Notice how the more molecules are separated as 40F gas than they were 40F fluid.
There have been huge changes in the density during this latent heating process. R-22 molecules will be about 52 times farther apart, as the gas in the liquid state. This division reasons to reduce the density of about 98% of what it was 40 yearsF fluid. State change causes a large change in the interval and agreement, but very little change in the speed of molecules.
Most of the heat is required to achieve this new distance and location of molecules, but it is not visible on the thermometer. This leaves warm refrigerant as long as couples. A fever you can't measure the distance and location of molecules in a substance. The heat that can be measured temperature can be implemented using a thermometer, and called sensible heat. Heat, that one cannot measure the temperature could not be implemented using a thermometer, and is called the latent heat. Latent heat is the amount of heat that is lost or absorbed by a substance, such as R-22 in order to change its state.
The total amount of heat contained in our sample R-22 gas 40F is equal to its sensible heat and latent heat. This is true of any substance. Often latent heat in Gaza more than sensible heat. For this reason, it is important refrigeration, that we measure total heat. This measure, expressed in BTU.
Technically, anything above about -460F (absolute zero) contains a certain amount of heat. Cool, so, really is a relative concept. From a human viewpoint, ice seems cold to the touch, because the temperature of the skin around 92F and ice 32F or below. Ice only cold compared with a finger.
Similarly, from the point of view of the outdoor unit, Central air conditioning system, 95F relatively cool air. R-22 refrigerant circulating through the tubes is about 120CF, which is much warmer than the outdoor air. Since the purpose of the mechanical refrigeration controls the movement of the heat right question to ask is : "How much heat does it contain?" ratherthan, "How cold is it?"..
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Refrigeration 
