A water cooler (commonly spelled "watercooler" as a compound word) is a device that cools and dispenses water. They are generally broken up in two categories: bottle-less and bottled water coolers. Bottle-less water coolers are hooked up to a water supply, while bottled water coolers require delivery (or self pick up) of water in large bottles from vendors.
The most common form of the water cooler is wall mounted and 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. Some versions are freestanding floor models, which are becoming more popular in countries where it is not common to drink water straight from the tap.
In the standard wall-mounted cooler, also commonly referred to as a water fountain or drinking fountain or in Wisconsin, a bubbler, a small tank in the machine holds chilled water so the user does not have to wait for chilled water. Water is delivered bsy 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. 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.
A newer, free-standing design involves bottles of water, usually treated in some way, placed spout-down into the dispensing machine. To install the bottle, the bottle is tipped upside down and set onto the dispenser, a probe punctures the cap of the bottle and allows the water to flow into the machines internal resivor. These machines come in different sizes and vary from table units, intended for occasional use to floor-mounted units intended for heavier use. Bottled Water normally is deliverd to the household or business on a regularly basis, where empty bottles are exchanged for full ones. Commonly a cup dispenser can be mounted to the side of the unit to keep disposable paper or plastic cups handy for use. The bottle size varies with the size of the unit with the larger versions in the US using 5 gallon bottles. The standard size elsewhere is 18.9 litres, and the containers are known in the beverage industry as 'bubble-tops', as bubbles raise and pop as the container fills. Some units offer a refrigeration function to chill the water. These units do not have a place to dump excess water, only offering a small basin to catch minor spills. On the front, a lever or push button dispenses the water into a cup held beneath the spighot. When the water container is empty, it is lifted off the top of the dispenser, and automatically seals to prevent any access water still in the bottle not to fall.
These gravity-powered systems have a device to dispense water in a controlled manner. Some versions also have a second dispenser that delivers room temperature water or even heated water that can be used for tea, hot chocolate, or instant coffee. The water in the alternate hot tap is generally heated with a heating element and a hot tank (much like the traditional hot water heaters used in residential homes). Additionally, the hot tap is equipped with a push-in safety valve to prevent burns from an accidental or inadvertent pressing of the lever.
When used in larger companies, staff somehow manage to show up at the same times during the workday. This informal gathering is often colloquially described as meeting "around the water cooler". Topics discussed during such meetings are said to have a "water cooler effect". This means that these topics are newsworthy current events or office gossip interesting (or important) enough to start off conversations around the water cooler. Television shows that people have conversations about are watercooler shows. Conversations around the water cooler are typically of a less professional nature than usual office conversation. Cartoons are commonly found of emplyees leaning on the water cooler, frequently refilling their disposable cup.