Is Booster Pump Needed??

[Golfdci681]

I recently had an irrigation system installed at my house, its on a well and runs about 5gpm. It's 600 feet deep. I tested the static pressure at my hose bib and got a reading of 65psi. Now my question is my installer put a 1.5 hp booster pump in for my irrigation. With a reading of 65psi static, do I even need to have the booster in place?

 

[PumpMd]

about 600 ft deep(how deep is the submersible pump set in your well?)

I have a 1HP pump(gpm pump end?) in my well.

The 3/4" Pex main water line needs to be bigger, so you can get more volume through the pipes to the heads.

I have 5 zones with 5 heads on each. You can change out the orifice size in the heads to match the submersible pump with more volume. If you have a 10gpm pump end in your well, 2gpm per head would keep the pump running. You already know you have the pressure, you just need more volume. Booster pump wouldn't be needed either.

 

[Sponsor]

 

[Reach4]

Static pressure is not the main factor. You want to know the pressure while drawing a known rate of water. As PumpMd points out, you would adjust your zones to draw accordingly.

It is good that you are looking into your odd system with its check valve between the pressure tank and the house.

 

[Golfdci681]

The pump is set at 400 feet inside the 600 well. It is a Gouls 5gpm pump

 

[Golfdci681]

The well drilling tag says that the well is 600 feet with a casing depth of 111 feet at 6in and it should produce 3 gpm

 

[Reach4]

This chart is for 5 GPM pumps at various horsepowers. What HP do you have? 1 HP? If you don't know, you can tell pretty much by measuring the current or checking the control box model if you have one.

Note that the depth to water is not the distance the pump is set at.

Shut-off PSI is the pressure when the pump is running, but no water is being lifted during the test, even to fill the pressure tank. That test can tell you approximately what your depth to water is, as long as you know the pump HP. You should not stay in that condition for long, because water flow cools the pump motor.

 

[Golfdci681]

I have a 1 HP. So if I am reading this chart correctly it is says that at around 400 feet where my pump is it is producing about 4 GPM running around 60 PSI? Being that my shut off is set to about 65 psi and draw is set to 30psi on my switch. Within that range I'm pumping out 4 gpm. Correct? Is that adequate to run my system without a booster pump?

 

[Reach4]

I have a 1 HP. So if I am reading this chart correctly it is says that at around 400 feet where my pump is it is producing about 4 GPM running around 60 PSI? Being that my shut off is set to about 65 psi and draw is set to 30psi on my switch. Within that range I'm pumping out 4 gpm. Correct?

Not quite. That would only apply when you are about ready to run out of water. Suppose your system is set to 40 to 60 for easy calculations. Suppose the static water level is 300 ft. Then ideally, at 50 PSI, your irrigation system would draw about 6.0 GPM. The pump would not cycle. If you were drawing a little more, the PSI would drop. What if you flushed a toilet in the house? The pressure would drop some. If the total draw went to 7 GPM, the water pressure could drop to 20 PSI. But the total GPM would probably not rise that much, because as the pressure started dropping, the sprinkler heads would start drawing less water.

There are graphs that let you figure out the flow for whatever conditions. They are not as easy to use as the tables, but they are more flexible. Alternatively, if you wanted the GPM at some other pressure, you could adjust the depth to water to get an equivalent. A 5 PSI pressure difference at the surface is the same as changing the depth to water by 11.53 ft.

Is that adequate to run my system without a booster pump?

It could be. It depends on the irrigation system... If you do use a booster pump, 2 HP seems very oversized. You could use a CSV on that booster output as a regulator, it seems to me. Then the sprinkler heads will see less variation of pressure.

I certainly would be looking to get rid of that check valve to the house. And if you keep that check valve, it seems to me that you would want a pressure tank after the check valve. But no check valve to the house seems best to me.

 

[Golfdci681]

I can remove the check valve to the house but should I install a check valve between the irrigation tie in and the irrigation pump itself because there is not one there? Thanks

 

[Reach4]

I can remove the check valve to the house but should I install a check valve between the irrigation tie in and the irrigation pump itself because there is not one there? Thanks

I don't know that you need a check valve. Did somebody say that you should put in a check valve? Maybe a check valve to the irrigation stuff could makes sense. In the case of irrigation from city water, they normally require something a lot more complex than a check valve I think.

 

[Golfdci681]

Ya just to the irrigation being either a anti sphion valve or some sort or either just a basic check or a double check. That way one it should stop the air from entering back in and also stop any sort of backflow for contamination. Thanks

 

[Valveman]

If the booster pump is just plumbed in line between the well pump and irrigation, just turn off the booster pump and see how the sprinklers work.