pressure switch cycling on and off constantly

I have replaced my old galvanized tank with a new bladder tank. Previously I had two seperate wells feeding the tank. When one got low, went to the breaker box and changed wells. Due to pitting and corrosion I replaced the tank with a new bladder model. There is now some 70 inches of copper between my pressure switches and the new tank. (someone said this may be an issue) One of the wells which is approx 425' deep works fine. The other which is 135' deep does not. The pressure switch rapidy turns on and off once the pressure in the system hits turn on pressure (20lbs). I have changed the switch. Any idea what is wrong?

Thanks in advance.

That usually means there is a serious water leak; like a leaking check/foot valve or a hole in the plumbing. It also proves the switch is working as designed.... The water is going somewhere or the pressure wouldn't fall.

You've not described your system enough to let us visualize it. You don't have both switches powered at the same time do you? If not, there is no need to balance the system and then the 70" has no bearing, so what is the concern about 70" of pipe between the switches?

If you have both switches powered, then I suggest you may need to hide them from each other with a check valve between them, but I'm not familar with runnng two wells with two switces. Maybe one switch with a contactor if you're going to run the two together? Or do as you as you did before and run one well at a time.

Try putting the switches at the tank. If that don't help, you may need a pulsation plug on each one.

bob..

What is the precharge on the new tank?

Experiment with the offending switch by raising the cut - out pressure until it stops cycling

If there is a valve between the switch and tank be sure its full open. valve handles position [used ones] do not always mean the ball or gate is actually moving with it.

If you had a leak it would never shut off.

switch should be closer to tank or extend water tubing to switch area to make same result.