Refrigeration
Refrigeration works by removing the heat from a product and then transferring the heat to the air outside.
A refrigeration system has five basic system components, which are:
- The Evaporator
- The Compressor
- The Condenser
- The Expansion Valve
- The Refrigerant (which conducts the heat from the product)
Each of these components must be present within the refrigeration system, for the refrigeration cycle to operate successfully.
The Evaporator removes unwanted heat from the product, through a liquid refrigerant which is boiling at a low-pressure. This pressure level is determined by two factors:
- The rate of heat absorption from the product to the liquid refrigerant in the evaporator
- The low-pressure vapour removal rate from the evaporator by the compressor
The Compressors purpose is to draw the low-temperature, low-pressure vapour from the evaporator through a suction line, which is then compressed, which will cause it to rise in temperature and release it through a discharge line.
The Condenser, with the use of fans, extracts heat from the refrigerant and expels it to the outside air. It is usual for the installation of the condenser to be located on a reinforced roof area.
The Expansion Valve is within the refrigeration system at the end of the liquid line and prior to the evaporator. Its purpose is to reduce the pressure of the refrigerant as it passes through, which reduces the temperature of the refrigerant to the ambient air temperature. This is then pumped into the evaporator.