Pump cycles on and off and pressure doesn't hold at 50psi with sink or shower on

[moxiemoney]

I have your CSV1A unit. I have a 1hp Franklin well pump, 10 gpm. On my CSV1A I have your small tank kit. Pressure switch is set at 40/60. I turn on my hose to about 2.5gpm output and adjust the CSV as instructed so that it is constant 50 PSI and holds fine. But when I go in the house and turn on just a sink or just a single shower, the well pump kicks on at 40psi and fills the pressure tank and PSI hits 60, and switch cuts off the pump, it then drains and cycles again. This means my pump is turning on and off every 15-20 seconds or so, which is what I'm trying to prevent. Shouldn't it hold at 50 psi regardless of if it's a single sink or shower? I don't want to burn out my new pump! Any help is appreciated. Thanks.

[Cary Austin]

Either you have the adjustment bolt on the CSV tightened in too far, or your sink and shower are not using a gallon per minute.  I would try to adjust the CSV while the shower is running instead.  You can also check the flow rate of the shower with a bucket test.  If the shower or sink doesn't let out at least 1.2 GPM, the CSV cannot keep the pump from cycling.  With a 10 GPM, 1HP pump that 1.2 GPM would be the minimum flow through the CSV.

If the shower and/or sink do not let out more than 1.2 GPM, you can remove or drill out the flow control washer in the shower head and the aerator in the sink.  Then you can have some strong pressure in the shower and the CSV will keep the pressure constant.