How a well water system works

The first thing to understand about delivering water to a building is that water is simply not compressible. So, pressure must be applied to water to get it to go anywhere. That pressure is applied to water in cities and towns through water towers. The weight of the water (approximately 7 lbs per gallon) applies tremendous pressure to push water through the pipes. A well needs a way to create and regulate pressure to be delivered to a building too. Without a pressure regulation system, water would be delivered to the home continuously at the maximum pressure of the well pump, which would create damaging stress on the pump and the pipes and fixtures throughout the home. So, a pressure regulator is added to the system, which turns on the well pump at a certain low pressure point and shuts the pump off at a high pressure point. A pressure regulator alone would spare the pump and pipes some stress, but the pressure of water flowing through faucets, shower heads and tub spigots would rise and fall noticeably. To smooth out the pressure, a pressure tank is added to the system. This tank contains water in the lower half and air in the upper half. When the pump comes on, the water level rises within the tank, which compresses the air over the water. When the set pressure point is reached and the pump shuts off, the compressed air over the water in the pressure tank continues to apply pressure against the top of the water to continue pushing water through the pipes. The combination of the pressure regulator and the pressure tank even out the water pressure to the point that one hardly notices when the pump comes on or shuts off. Whenever the water pressure begins to noticeably fluctuate, one can assume that one of the components of the pressure regulation system is failing.