Yes, where you tap into your water well system does matter. If you tap into your system before the pressure storage tank, it will eventually not only effect your household water pressure but can lead to eventual pump damange. The "Tank" is not only a storage tank for water, but also your hous water pressure. Most storage tanks work by holding water and vapor pressure in the tank for use when someone opens up a valve inside the home. Once a tap is opened up, water moves from the tank to the point of opening and at the same time the pressure in the tank falls. Once the pressure falls below the set point of the pressure regulator, it starts the pump and the tank begins to refil. Since the water line from the tank to the pump is empty, the first thing that enters the tank is vapor pressure. Once all the air has moved from the water line to the tank and the line fills with water, the tank begins to fill. Once the water demand has ended, the tank will continue to fill until it reaches the set point of the pressure regulator which will trip, turning the pump off. A check valve which will probably be installed on the water line coming into the pump, but close the the pump will close, preventing water from the tank draining back into the water line. A air valve (looks similar to valve stem on a car tire) opens up and allows air to enter the water line which releases the vacuum in the line and lets the water in the line to drain back down into the water well. When additional demand for water happens, this valve closes and the pump is activated, and again the air that is now inside the tank rushes into the tank ahead of the water. This air creates a vapor space inside the tank which creates a more constant water pressure inside the house. Without this system, your water pump would kick on every time someone opens a tap inside the home, and would cause the pump to run unneccessarily. This will shorten the life of the pump dramatically. If you tap your irrigation system into the water line upstream of the tank, and you turn your irrigation system on, you will get an initial rush of air out of the spray heads and eventually water. Once the watering stops and the valves close, the water line will not be able to refill with air. Thus, once water demand happens from within the house, the line will still be full of water and will not refull the tank with air. Eventually your tank will become water logged and your water pressure will be effected which will cause your pump to run all the time. Sorry for the long reply, but couldn't find a short version of explaining this. Sincerely, Curtis Anderson Evergreen Sprinklers Here is a link that might be useful: EvergreenSprinklers.com

Update; 4 hours of messing with this thing, I finally gave up and went to my local 'warehouse' style lumber lumber yard and bought a new pressure switch. $27 and 30 minutes later, life is good again! Yes I bought a new gauge, since I was banging on the thing to get it to move.... Now just to stop that relief valve from dripping... Probably just need to remove and flush it, since I replaced it last month. There was 'so much' crud filled into the pipe to the pressure switch, no wonder it wasn't working right. Thank God I have the new filtering system up and running (new 2 years ago). Don't wish to think what's been happening to all the other appliances I have here. Oh the joys of home ownership and living in the country!

I had the same situation as you in a summer place. My electrical panel was in the kitchen. When I was going to be away, I shut off the breaker. If I remember right, the pump and the pressure switch are interconnected and wired on the same breaker. So, if you shut off that one breaker, eveything is off and you are safe. You are correct...if something let loose, you could either flood the place or burn out the pump. Why have it on if it's not needed. When I am going to be away from my residence for a week or so, I turn off the water to the house. In a home, I think the most likely thing to break is the rubber hoses to the washing machine.

The tall screw changes both the cut-in and cut-out switch settings equally; raises or lowers both together. The short one changes only the cut-out up or down. Tightening (CW-right) either raises the pressure and loosening (CCW-left) either lowers the pressure. All switches require a 20 psi minimum differential. I.E. 30/50, 40/60 etc.. All well water systems should have as most do, a 75 psi pressure relief valve on the pressure tank. It is not a good idea to set the pressure higher than 65 psi. The pressure tank's precharge captive air pressure provides the power to move water when the pump is off. Thereby it is critical to get it right based on the cut-in setting of the switch. You set it with no water in the tank. I.E 30/50 psi water pressure switch settings gets 29-28 psi air pressure with no water in the tank. Incorrect air pressure is the primary cause of pressure tank failure. It will cause short cycling of the pump and that is the primary cause of pump motor failure. The best way to protect a pump is to install a CSV (www.CycleStopValve.com) They give you constant pressure and much longer pump life because they come on like all pumps but then run continuously until the water use falls to .5 gpm. Then the pressure rises to cut-out as it fills the tank and the pump shuts off. ALL well pumps are rated for continuous duty. It takes more electric to start and stop a pump than if you keep it running once started. All pressure switches are adjustable, yes even though.... you buy them today preset at 20/40, 30/50 or 40/60 psi. They are all the same switch; mostly Square D or Furnas. Furnas doesn't have the short spring screw, it has a bolt head and the switch is blue instead of Square D's gray. The wider the differential of the switch (30-65 etc.) the more noticeable the pressure fluctuation is.