I have a brass pressure vavle located at the top of my well, and when the pump kicks on,I hear air but get no water. How do I fix this or is there another reason I'm not getting water.system is 3yrs old and deep well 370 ft,1 3/4 hp motor

Most deep wells have two lines connected a the bottum with a foot valve whitch may be stuck or the pump may have lost it's prime

Show us a picture of that valve.