Although it’s commonly used to describe sweet, fizzy beverages like Coke, Pepsi and Dr. Pepper, the term “soda” most specifically refers to the root cause of soda’s fizziness, the bubbly sodium bicarbonate solution — “soda water” — you mix with concentrated flavor syrups to concoct it. Also known as carbonation, this ingredient is arguably central to soda’s goodness; without it, after all, you’d just be drinking diluted sugar. If you own a soda fountain, or work around one, and believe the machine’s carbonator tank might be faulty, you need to test it out to make sure.

Things You'll Need

Check your carbonator tank. Read the carbon dioxide gauge on top of the tank and make sure it’s adequately full; more than 25% is ideal. Although many other soda machine malfunctions can cause issues with carbonation, even a brand new machine can’t remedy an empty tank.

Sample a small glass of soda water to ensure adequate carbon dioxide is flowing through the machine’s water. Locate the “Soda” tab on the fountain, which will be located beside one of the proper soda beverage dispensers. Place your glass under the appropriate nozzle, then hold down on the “Soda” tab for a few seconds. Drink the soda water, keeping in mind that pure soda water should be extremely fizzy; if you’re not used to drinking it, it might even make your mouth uncomfortable.

Test each individual beverage to ensure there are no issues with the individual carbonation lines leading to each flavor’s dispenser. Pour a very small amount of each soda into a cup and sample it, keeping in mind that the soda’s sweetness and fizziness should balance each another out. If you feel overwhelmed by the sweetness of any given soda, there is a problem with one of the carbonation lines.