* Refrigeration is a process in which work is done to move heat from one location to another. The work of heat transport is traditionally driven by mechanical work , but can also be driven by heat, magnetism , electricity , laser , or other means. -Evaporator : The evaporator is where the heat is removed from your house , business or refrigeration box. * Two different pressures exist in the refrigeration cycle. The evaporator or low pressure, in the "low side" and the condenser, or high pressure, in the "high side". These pressure areas are divided by the other two components. On one end, is the metering device which controls the refrigerant flow, and on the other end, is the compressor. * -Compressor : The compressor is the heart of the system. It compresses the low pressure refrigerant vapor from the evaporator and compresses it into a high pressure vapor. -Condenser:The hot vapor enters the condenser and changes to liquid. -The Metering Device: A very common type of metering device is called a TX Valve (Thermostatic Expansion Valve). This valve has the capability of controlling the refrigerant flow(lowering pressure) : : Mrs . S a r a * has many applications, including, but not limited to: household refrigerators , industrial freezers , cryogenics , and air conditioning . Heat pumps may use the heat output of the refrigeration process, and also may be designed to be reversible, but are otherwise similar to refrigeration units.