What is a Refrigerator
A refrigerator is a common household appliance that transfers heat from the inside of the device to the area surrounding it, resulting in the fridge’s temperature being lower than that of the room. Refrigerators (also known as fridges) have been used extensively for food storage since they replaced the icebox which had been the go-to food storage household for appliance for over a hundred years.
A refrigerator consists of a heat pump that enables the transfer of heat, and a thermally insulated compartment that serves as the inside of the device, and a holding area for all the items that need to be preserved at low temperatures. Typically, a refrigerator is kept a few degrees above the freezing point of water for optimal storage of perishable foods. A related device that maintains a temperature below the freezing point of water is known as a freezer.
History of Refrigerators
Prior to the invention of refrigerators, icehouses, melted snow and other natural means were used to preserve food. There were several technological advances in the field of artificial refrigeration in the 18th through to the 20th century, particularly noteworthy among them being:
1755 – Scottish professor William Cullen invents small refrigerating machine to demonstrate that the rapid heating of liquid to a gas can result in cooling, a principle still used today in modern refrigeration technology.
1802 – American businessman, Thomas Moore, invents icebox to cool dairy products for transport. He called his invention a refrigiratory until 1803 when he secured the patent for refrigerator.
1820 – Michael Faraday uses high pressures and low temperatures to achieve liquefication of ammonia and other gases.
1834 – Jacob Perkin creates first working vapor compression refrigeration system.
1842 – John Gorrie builds a working prototype based on Perkin’s model which failed commercially.
1840s – This decade saw carpenters create the first iceboxes, insulated wooden boxes lined with tin or zinc and used to hold blocks of ice to keep the food cool.
1859 – Frenchman Ferdinand Carré develops aqua ammonia, the first gas absorption refrigeration system using gaseous ammonia dissolved in water. He patents it the following year.
1876 – Carl Von Linde, an engineering professor at the Technological University Munich in Germany patented an improved process of liquefying gas that has become part of basic refrigeration technology.
1913 – The first set of domestic and home use refrigerators were invented by Indiana’s Fred W. Wolf, consisting of a unit mounted on an ice box. His model was called the Domeire or DOMestic ELectric REfrigerator.
1916 – Alfred Mellowes invents a self-contained refrigerator, with a compressor on the bottom of the cabinet. His invention was made commercially available.
1912 – William C. Durant buys out Mellowes and starts Frigidaire, a company that set out to mass produce refrigerators based on Mellowes invention.
1918 – The Kelvinator Company introduces the first set of refrigerators with an automatic control system, based Nathan Wales’ idea for a practical refrigeration unit.
1922 – A collaborative effort between Swedish students Baltzar von Platen and Carl Munters created the absorption refrigerator. The model was regarded as a worldwide success and commercialized by AB Arctic in 1923. Ab Arctic was acquired by Electrolux in 1925.
1923 – Frigidaire introduces the first self-contained refrigerator units.
1927 – The General Electric introduces the “Monitor-Top” refrigerator, which used as a refrigerant either sulfur dioxide or methyl formate both of which are potentially harmful in the event of a leak. The Monitor-Top was the first refrigerator to see widespread use with over a million units shipped.
1930 – Albert Einstein and Leó Szilárd together patented the Einstein Refrigerator, a new design that featured no moving parts and operated at a constant pressure.
1930s – Freon was introduced as a refrigerant alternative providing a safer, low-toxicity alternative to established options. Freon quickly became the standard for most domestic refrigerator offerings and was instrumental to the drastic expansion of refrigerator market share.
1945 – The post-World War II era saw full mass production of modern refrigerators. By the 1950s up to 90% of modern American homes and 80% of the farms had a refrigerator unit, but in Britain a mere 2% of households had one.
1970s – The eyes of the world turned to focus more on the environment and keeping it safe, and so Freon was indicated as a threat to the ozone layer. Research into alternatives resumed in earnest, and Freon as a refrigerant was eventually phased out completely in the 1990s.
Features of a Modern Refrigerator
- Some features that may be found in newer refrigerator models include:
- Automatic defrosting
- A power failure warning that alerts the user by flashing a temperature display.
- Chilled water and ice from a dispenser in the door.
- Cabinet rollers that lets the refrigerator roll out for easier cleaning
- Adjustable shelves and trays
- A status indicator that notifies when it is time to change the water filter
- A removable in-door ice caddy.
- A cooling zone in the refrigerator door shelves.
- A Fast Freeze function to rapidly cool foods.
Components of a Refrigerator
Below are the components you will find in most modern refrigerators
THERMOSTATIC EXPANSION VALVE (TXV)
The TXV is a device that controls the amount of refrigerant that flows to the evaporator.
This component is responsible for removing the unwanted heat from the product through liquid refrigerants which is required to be at a low pressure.
Capacity Control System
The capacity control system regulates the power and energy consumption, although it can also manage dehumidification or decrease compressor cycling. The most basic form of capacity control in a refrigerator is the on/off cycling of the compressor.
The compressor’s job is to draw low temperature and low pressure vapour from the evaporator through the suction line so that heat can be easily released.
The condenser extracts heat from the refrigerant.
The receiver’s primary purpose is preserving the vapour moving down the liquid line to the expansion valve. If you want to buy a used refrigerated van, a used freezer van, a new refrigerated van or a new freezer van call, Glacier Vehicles on 0208 668 7579.