I just bought all new stuff. I have a jet pump at shallow well with foot valve set-up, check valve about 1 ft from outlet, pressure switch mounted on pump. Tank is located in house with all proper fittings called for with manual. My pressure switch has stopped working. At first it just wouldn't come back on but if I hit the little button located on the pressure switch it would come on so I used WD40 on the button because it seemed to be getting stuck it worked for a couple of days but now it won't shut off pushing the button or pulling the button does nothing. I went and bought a new pressure switch(20/40psi which is the same for tank)This switch does the machine gun thing the entire time its pumping until 40 psi shuts off and won't come back on. Also I noticed that when the pressure tank is full and water is used when the gauge on the tank gets to 20psi the needle in the gauge drops to 0 and running water stops and tank seems to be empty. Please help me I'm am very frustrated with this because I finally have everything set up as it should be (nothing rigged) and it still isn't working I have learned many many lessons the hard way in the past few years of having a well fed house.