Aspirin, also known as acetylsalicylic acid (ASA), is a salicylate medication, often used to treat pain, fever, and inflammation. Aspirin also has an antiplatelet effect by stopping the binding together of platelets and preventing a patch over damaged walls of blood vessels.
The device, which connects to the plumbing, regulates the home's water supply. When the water pressure drops to a certain level, the switch senses more water is needed, and spring-loaded electrical parts make contact, turning on the well pump. When the pressure returns to a preset level and the well tank is filled, the electrical contacts separate, and the well pump turns off.
If it is not showing a pressure of 30-50 psi or 40-60 psi (slightly left of center) that could be your problem. The electrical switch at the pressure tank (grey box) is a fairly common cause of failure in the pump/private well water system; so check the switch to make sure it is working. Manually closing the pressure control switch should turn the pump on.