Pressure Switch Bouncing after cut off

[Stacks056]

Hi,

I'm new here, but I have been battling a new pump installation on a shallow well for about 3 months and I'm almost done except for a small issue when the pump cuts off. 

I have a Zoeller 1hp shallow well pump converted for a deep well setup.  The well is 30ft deep.  The pump is above ground and outside of the well obviously.  From the pump I have 3/4" pipe (manufacturer recommended) running to a 1" Tee to a 1-1/4" pressure tank opening.  It's about 4ft of pipe length from the pump outlet to the Tee setup.  I'm using a pressure switch (30/50) mounted on the pump itself.

In line from the pump to the tank is a shut off ball valve BV, and a check valve CV, both are brass and the CV is a spring style. On the Tee my pressure gauge is first and I have another pressure switch mounted to the port just downstream from tank, but still on the Tee.  I elected not to use this switch just to avoid the length of wiring, thinking that using the switch mounted to the pump would be keeping it simple. Also, the switch mounted to the pump seems to be of higher quality than the kind you get at Lowes.

I also have no leaks that I can see at all, at the moment.

The pump fills the tank to 50psi and then cuts off.  The pressure gauge mounted to the pump, next to the PS mounted to the pump, then drops quickly well below 30 and the pump kicks on again, shooting pressure back to 50 where it cuts off again.  It does this 5 or 6 times but I didn't want to harm my pump so I turn it off right away, I'm not sure if it would cycle like this forever, or if it would eventually even out.

I have read that a CV in between the Pump and Tank can cause this.  With the idea being that the pump stops, then the CV closes a moment after ward due to the tank pressure, resulting in pressure below 30psi in that length of pipe going back to the pump.  But I have also read that the pressure switch should be as close to the tank as possible because it will experience more constant pressure.   

Does anyone see an issue with what my setup is?

Should I remove the CV? Or should I use the Switch on the Tee?

[Cary Austin]

Your biggest problem is that you have a check valve between the tank and the switch.  Remove that check valve.  There must be a foot valve at the bottom of a deep well ejector, and that is the only check valve you want in the system.  You also may need to use the pressure switch that is closer to the tank, but it may work on the side of the pump once you remove the check valve.

[Stacks056]

Ok, I will definitely remove that check valve and see how she flies. 

on a separate note though, I have a check valve in the 1" line going into the well, and a check valve in the 1-1/4" line coming out of the well.  I'm hearing you day this is overkill, but are they harmful or can they stay? haha

[Cary Austin]

Again, the only check valve you want is the foot valve below the ejector.  Any other check valve in the line will cause a momentary drop in pressure or a complete loss of prime.