I tried calling customer service and was on hold for a very long time. Hope someone here can provide me with an answer. Underneath the actuator box, there is a switch than can be moved in 3 positions. Front, middle, back. One of the positions, I forget which one off hand, closes the valve automatically. What are the other two positions? Maybe you can tell me the three positions since I don't remember which one closes it. Just want to make sure it is working properly. Thank you.