There are two primary methods of filling water bottles. The traditional method is to use gravity. Bottles are filled by lifting them with the filler up, and letting the bottle fill on its own. An alternative method is to pump water into bottles.
A typical water cooler can house upwards of 8 individual hot or cold fountains which all share one inlet supply line connected to a large tank of source water kept at 50°F (10°C)
The typical system will deliver about 4-5 gallon/min (15 liters/min). While this quantity will vary, it’s not uncommon for speeds to be upwards of 10 gallons per minute (40 liters).