Request for comments on well pump and tank selections

[cootcraig]

Information on the well:
Yield of 7-8 gpm. I measured over a 1 hour flow test.
7" casing
depth of well: 40 ft.
depth of pump: 36ft.
depth of water 23 ft.

current pump is:
Myers Pentair Water "The Rustler"
Model #: 3NFL102-20-P4-01
1 HP. 20gpm. 3 Wire. 230V. single phase.

The well is used to irrigate the property and supply 4 yard faucets.

With pressure from irrigating the spray is strong at first, but drops off after a few minutes to not enough flow/psi for the sprinklers. I have a sonic water depth tester and there is water in the casing when the sprinklers stop.

I plan to install a Cycle Stop Valves PK1A Kit

with a CSV1A pressure setting of 50psi and a dole valve to limit flow.

The performance log of the Grundfos 10S05-9 Pump looks to be a good match for my use.

After reading through this thread Who Makes the Best Submersible Pump?

I am considering this pump sourced from envisupply.com. Their well expert says he has sold combinations like this before. I may not have the part particulars right.

Franklin 2145059004GS Motor
Franklin 2801054915 Control Box
Grundfos 10S05-9 Pump End 9010009

As an alternative, what about using the Grundfos 10S05-9 Pump End with the current 1 HP myers motor?

 

[Valveman]

There is probably nothing wrong with the 20 GPM, 1HP pump you have now. The point of the CSV in the PK1A is to make a large pump work like a smaller pump when needed. The CSV will make the 20 GPM pump work like a 7 GPM pump, so you won't pump the well dry, which is what I think is happening. With only 13' of water in the well and a 20 GPM pump, you are probably pumping the well dry while filling the pressure tank. Assuming you are using a pressure tank, it should hold about 20 gallons of water, which would deplete the well.

Once the well is pumped off, the pump may stop pumping or just pump a small amount until you shut off the pump and restart it. Even though you may only be running 7 GPM sprinklers, the pump is pumping 20 GPM, then it is off for 3 minutes and does it again. But you don't have enough water in the well to fill the tank and run the sprinklers at the same time, so it pumps the well off and you lose prime.

A CSV, as comes in the PK1A, will make your 20 GPM pump into a 7 GPM pump when you only put out 7 GPM worth of sprinklers. You don't even need a Dole valve. Just run 7 GPM sprinklers and the CSV becomes a 7 GPM valve. The CSV system just starts the pump at 7 GPM and is not filling a tank at the same time, so you should not pump the well off.

What you really need is a Cycle Senor to protect the pump in case you open up more than 7 GPM and pump the well dry.

 

[Sponsor]

 

[cootcraig]

With only 13' of water in the well and a 20 GPM pump, you are probably pumping the well dry while filling the pressure tank.

No pressure tank. Water depth 24ft. when the zone started, and at 26 ft. when the sprinklers shutdown with pump powered.

Even though you may only be running 7 GPM sprinklers

I didn't put the sprinkler system in and don't know the flow rate. Eventually I will redo the sprinkler zones to match the well output.

What you really need is a Cycle Senor to protect the pump in case you open up more than 7 GPM and pump the well dry.

Agree.

 

[cootcraig]

A CSV, as comes in the PK1A, will make your 20 GPM pump into a 7 GPM pump when you only put out 7 GPM worth of sprinklers. You don't even need a Dole valve.

My hope was that the irrigation could be used over the summer and then install the PK1A kit in the fall. Your suggestion of installing the PK1A with current pump sounds like a good idea.

 

[Valveman]

No matter how you control it, you just can't pump more than 7 GPM if your well only makes 7 GPM.