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How Kegerators Work

From Keg to Tap

Kegerators are a remarkably simple system, and regardless of shape or size, they should all have the same basic components:

  • Carbon dioxide (CO2) cylinder
  • Carbon dioxide regulator
  • Coupler
  • Tubing (special carbon dioxide tubing as well as line for the beer)
  • Keg
  • Faucet
  • Refrigerator

A kegerator works by applying carbon dioxide pressure on the keg in order to push the beer upward and out of it. Although carbon dioxide is a natural by-product of fermentation, the cylinder allows for constant and even pressure to be applied to the keg while it's tapped. This helps maintain consistency and carbonation. The cylinder filled with carbon dioxide is connected to a regulator, an instrument that allows you to change the pressure. The coupler, or the valve that taps the keg and allows beer to flow from it, uses a separate tubing input and output. One tube leads from the regulator to the "in" part of the coupler, and another tube runs from the "out" part of the coupler and ends at the faucet, out of which the beer is poured into your cup. The keg is usually stored inside a refrigerator, which has the faucet on the outside.

One of the main benefits of the kegerator is its ability to keep beer fresh for long periods of time. Beer stored in a kegerator should stay fresh for at least one month, but it can stay good for up to four months if the keg is kept pressurized and properly cooled [sources: BYO, Kegerators]. Several components factor into beer spoilage, but you'll learn more about that later in this article.

The most important facet in dispensing a perfect glass of fresh beer is the temperature. This is where a standard keg in someone's backyard falls short. But because the keg in a kegerator is kept refrigerated, this is easy to regulate. Most beer that is stored cold is kept at about 36 to 40 degrees Fahrenheit (2.2 to 4.4 Celsius), although this changes from beer to beer. Storing it at a temperature that is too high or too low can affect the beer's flavor [source: Anheuser-Busch]. Measuring the temperature can be done in number of ways: Some prebuilt kegerators may come with a temperature gauge, but for the thrifty, a glass of water with a thermometer kept in the kegerator can give an accurate reading.

If a kegerator sounds like the kind of thing you'd like to have in your home, read on to discover what options are available.