A water dispenser, sometimes referred to as a water cooler (if used for cooling only), is a machine that dispenses and often also cools or heats up water with a refrigeration unit. It is commonly located near the restroom due to closer access to plumbing. A drain line is also provided from the water cooler into the sewer system. Water dispensers come in a variety of form factors, ranging from wall-mounted to bottle filler water dispenser combination units, to bi-level units and other formats. They are generally broken up into two categories: point-of-use (POU) water dispensers and bottled water dispensers. POU water dispensers are connected to a water supply, while bottled water dispensers require delivery (or self-pick-up) of water in large bottles from vendors. Bottled water dispensers can be top-mounted or bottom-loaded, depending on the design of the model. Bottled water dispensers typically use 5-gallon (18.9 litre) bottles (carboys) commonly located on top of the unit. Pressure coolers are a subcategory of water dispensers encompassing drinking water fountains and direct-piping water dispensers. Water cooler may also refer to a primitive device for keeping water cool.
History The water dispenser was first invented in 1906 by Luther Haws.
Dispenser types
Wall-mounted / recessed
The wall-mounted type is connected to the building's water supply for a continuous supply of water and electricity to run a refrigeration unit to cool the incoming water, and to the building's waste disposal system to dispose of unused water. Wall-mounted water coolers are frequently used in commercial buildings like hospitals, schools, businesses, and other facilities where a facility manager is present to monitor its installation and maintenance. In the standard wall-mounted cooler, also commonly referred to as a water fountain or drinking fountain, a small tank in the machine holds chilled water so the user does not have to wait for chilled water. Water is delivered by turning or pressing a button on a spring-loaded valve located on the top of the unit, that turns off the water when released. Some devices also offer a large button on the front or side. Newer machines may not have a button at all; instead, a sensor that detects when someone is near and activates the water. Water is delivered in a stream that arches up, allowing the user to drink directly from the top of the stream of water. These devices usually dispense water directly from the municipal water supply, without treatment or filtering. Wall mount water coolers come in a wide variety of styles, from recessed models to splash resistant, contoured basins protruding out from the wall, traditional rounded square edge designs, bottle filler and water cooler combination units, bi-level designs, with other features and options. These are sometimes installed to meet local, state or federal codes.
Bottom-load water dispenser
Water dispensers commonly have the water supply vessel mounted at the top of the unit. Bottom-load water dispensers have the vessel mounted at the bottom of the unit to make loading easier.
Tabletop water dispenser
There are also smaller versions of the water dispensers where the dispenser can be placed directly on top of a table. These dispensers are commonly classified as household appliances and can often be found in household kitchens and office pantries.
Direct-piping water dispenser (POU) Water dispensers can be directly connected to the in-house water source for continuous dispensing of hot and cold drinking water. It is commonly referred to as POU (point of use) water dispensers. POU units are generally more hygienic than bottled water coolers, provided the end user has access to clean water sources.
Freestanding
A freestanding design generally involves bottles of water placed spout-down into the dispensing machine. Tabletop or kitchen worktop versions are available which utilize readily available five-liter water bottles from supermarkets. These coolers use air pumps to push the water into the cooling chamber and Peltier devices to chill the water. New development within the water cooler market is the advent of countertop appliances which are connected to the mains and provide an instant supply of not only chilled water but also hot and boiling water. This is often visible in the horeca industry. Water will flow faster when the handle is in the upright position. The water is aerated which allows the water to come through the spout at a faster rate.
Water source Water dispensed from water coolers may originate from many different sources, but are often classified into two major categories, namely natural mineral and spring water, and purified water.
Natural mineral and spring water Natural mineral and spring water are waters emanating from underground geological rock formations collected from boreholes or emerging springs. Legislation in each respective country further differentiates between these two types of water and stipulates strict naming and labeling criteria based on natural source protection, total dissolved solids, and the amount of processing the water may undergo prior to bottling.
Purified water Purified water is water from groundwater or municipal water supply and is produced by any one of several methods of purification including reverse osmosis, distillation, deionization, and filtration. The water is often treated by ultraviolet light or ozone for antimicrobial reasons and re-mineralized by injection of soluble inorganic salts.
Water delivery The delivery of water in a water cooler comes in two main forms, namely bottled variants, or plumbed directly from the main water supply. The water is normally pumped into a water tank to be heated or chilled, depending on the model of the water cooler. Modern versions include hybrid models that are able to utilize both methods.
Bottled water coolers
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