What exactly is a submersible pump?
A submersible consists of a small-diameter motor mated to a pump. The assembly is installed submerged in the water, down inside the well casing. Most residential wells use a four-inch casing, with the submersible being three and a half inches in diameter. Commercial or high-production wells and pumps are larger diameter. Length of the submersible varies, with higher horsepower, higher-output units being longer. For example, a half-horsepower (HP), five gallons per minute (GPM) submersible is about two feet long, and a 2 HP, 10 GPM submersible is about four feet long. There are many combinations of pump and motors, and the choice of the combination is critical. Obviously the units need to be more powerful for deeper wells, or if higher water production is desired. Special models are sometimes used for off-grid power applications. It’s also important to consider the velocity of the water being pushed to the surface. It must move at sufficient speed to carry solids (like sand, if present)
