Modern hand pumps like Simple Pump or Bison tell us to drill a small 1/8" 3mm hole in the water riser pipe that will allow water to slowly drain back into the well a few feet deep. This works because on these pumps, the working cylinder is all the way at the bottom of the well pushing water up from the bottom. Yes a tiny amount of water leaks out when you pump but it is worth it because it prevents freezing.

Submersible pumps go all the way to the bottom of the well. They have a set of wires that go all the way to the bottom to supply them with power. Look carefully and you realize that the motor is on the very bottom so it can be cooled by water flowing past it. These pumps should not run dry because they will overheat, so you should put a float switch in the well a few feet above the pump. Some pumps like Grundfoss have this switch built in.

In most places this is the most common type of pump. They can be two wire or three wire. The three wire models require a small electronics box up top with a capacitor in it. The reason for this is so you can service the capacitor without pulling the pump.

*two wire means two wires and a grounding wire. Three wire means three wires and a grounding wire.

The original versions of this system didn't use bladders but they did have a way to make sure that enough air stayed in the tank! Remember a few days ago we talked about freeze proofing with a weep hole? When the pump shuts off, the well leaks down a little and we get air into the piping. When the pump runs again, that air gets pushed into the tank along with the water from well. There is a valve inside the tank about half way up called "air volume control valve" that makes sure the tank stays half full of air and lets out any excess air.