Problems adjusting CSV

[DStyduhar]

Hi all,

Installed a new sub pump, hose, wires and CSV last weekend but struggling with adjusting pressure on CSV. The CSV is at the well head and the pressure tank/switch/gauge is in the house. Everything below is with our one shower running

1. When I am adjusting the CSV, it takes minutes before the change becomes apparent on the gauge in the house. I mean, I can take the bolt completely out and it seriously takes like 20 minutes for the gauge pressure to show change of 10 psi. This doesn't seem normal. There IS another check valve in the house between the CSV and pressure tank/switch/gauge so not sure if that is causing any issues.

2. Also, with the CSV bolt all the way completely removed, I have only seen as low as 40psi, not the 15-25 as indicated in the installation manual.

Please advise.

Drew

 

[Valveman]

Measure how much the shower is putting out with a bucket. If it is putting out over 2 GPM, the pressure should lower very quickly. If it is just a low flow shower head and not putting out much water, it will take a long time after loosening the bolt on the CSV for the pressure to drop. Try running a sink faucet along with the shower and see how quickly the pressure will drop.

 

[Sponsor]

 

[DStyduhar]

The shower was putting out a little less than 2 Gallons per minute. We ended up turning the shower on AND another faucet while adjusting the CSV and the pressure reacted twice as fast as before but still prob 1psi change per minute. The videos I have seen where folks are adjusting their CSV show it moving very quickly, within seconds.

So, we adjusted the CSV pressure to 55psi with the shower and faucet running. But with just the shower running, the pressure would go to 60, pump turn off, on and repeat. Here is something I am trying to wrap my head around.....how can the CSV be adjusted for usage if it varies throughout the day? I get if it were sprinklers where it only does one thing but how about a household where someone is in the shower and then the dishwasher is running and someone decides to flush a toilet.....?

thanks,

Drew

 

[Reach4]

The shower was putting out a little less than 2 Gallons per minute. We ended up turning the shower on AND another faucet while adjusting the CSV and the pressure reacted twice as fast as before but still prob 1psi change per minute. The videos I have seen where folks are adjusting their CSV show it moving very quickly, within seconds.

I suspect those people were using a significantly smaller pressure tank. How big is your pressure tank?

 

[DStyduhar]

one of those waist high units. Cant see the info as the label is right against the wall. Looks like 36 gallon.

 

[Reach4]

I would do one of these.

1. Increase the water flow to about 8gpm or 80% of what the pump can produce, whichever is less. Then reduce the flow for the fine tuning.
2. Count turns, and don't lose track. Stay with the 2 gpm, but graph the accumulated turns vs settled-down PSI. Once you have 2 data points, draw a line. Use the line to select your next screw turns. Stabilize, and add the new point to your graph. I suspect you will be where you want to be pretty fast. If you are spreadsheet expert, consider the curve fitting feature.
3. Same as #2, but use an interpolation calculator.
   https://www.johndcook.com/interpolator.html simple linear interpolate for two known points to compute the third.
   https://www.johndcook.com/quadratic_interpolator.html for 3 known points to compute the 4th.
   

My comments are not based on experience.

 

[DStyduhar]

Is it possible to bypass the CSV (without removing) to make sure the pump install and everything appears OK before fine tuning the CSV?

 

[Valveman]

With a little pressure tank any adjustment to the CSV shows a quick response. With a larger tank like yours, you have to wait for the tank to drain before the pressure will decrease, and for the tank to fill before the pressure will increase. The CSV still works fine with the larger tank, you just have to watch it longer to make sure it isn't creeping up in pressure. It is very easy to adjust the CSV for too high pressure with a large tank. If the pressure creeps up with a 2 GPM shower running, you just tightened the bolt on the CSV too far. Back it off so it holds about 2-3 PSI below the pressure switch off point while you are running the 2 GPM shower.

Tighten the bolt on the CSV a couple full turns to the right and it will just act like a piece of pipe.