RO feedpump

[Bmeehan19]

I have a procon 240gph pump feeding my 4x400gpd membranes. I will have a recirculating line. What can/should I use for a feed pump. I know since I will be recirculating I won’t be actually flowing 4gpm out of the system so would a 3gpm shurflo pump work, or should I get a shallow well pump, if so how many gpm? Could you let me know what pumps you use or recommend for me to get? Another consideration is during a rinse/flush I guess I may be actually flowing the full 4gpm. Thanks in advance.

Bryan

[mol1jb]

Finding a 4gpm pump should be easy. Shurflo largest pump is 4048 and that is 4gpm.

I wouldn't go lower flow than that as you eluded to on rinse and wash

Another consideration would be to elevate the feed tank as gravity feed is enough to keep the procon supplied. I have done it both ways but I do prefer the feed pump.

[bowhunter]

I run with an elevated feed tank for my ProCon pump and it works fine. You do have to change the feed filter more often because you don't have a pressurized feed system. The ProCon pumps in this size range have a lift of about 6 feet so they are ok with no feed pump. I have a Shurflo pump on my RO system that I use to transfer sap between various tanks, etc. The problem I see is it would be constantly kicking on and off during normal operation because the flow would be so low. If people on the forum are using a Shurflo to feed their RO with success then it might be a good option. It would generally be better to use a centrifugal pump as a feed pump because they can operate at many different rates of flow. One downside to consider when planning to add a feed pump is to make absolutely certain you keep the prefilter changed often enough. Several people on the forum have collapsed the filter element because the filter got dirty and the pressure of the feed pump destroyed the element. The pieces of filter wrecked the ProCon pump. If you use gravity to feed the RO you can generally tell if the filter is getting dirty because the ProCon will start to make a little rattling noise occasionally. When this happens you just have to replace the filter at the next convenient time. In the meantime you can just slow down the RO until you stop the stop the rattling. This is much less damaging to the ProCon than driving a piece of the filter element through the pump. The suction side of ProCon can not develop enough differential pressure across the filter element to crush it.

[Bmeehan19]

Thank you for the replies. I am torn between the shurflo and a shallow well pump for the reasons you describe. If I added a sort of bypass before the prefilter from the feedpump I could essentially dial it in to not keep kicking on and off right? Just have the bypass go back to the feed tank.

[Bmeehan19]

So I picked up a shallow well pump and it is rated for 10gpm. Now that will be significantly more than my RO will he processing. My procon is rated for 4gpm but when it’s pressurized and recirculated I will be putting out like .5gpm. My well pump has a pressure switch and I don’t want it to cycle repeatedly. How have people dealt with this scenario? Do I recirc the feed pump back to the tank to allow it to flow and to eliminate cycling? Do I just turn the pressure switch way down or override it?

The reason I went with this pump as I plan to expand to a 4x40 or in the next year or 2 so I wouldn’t have to buy another feed pump then. 20717

[Bmeehan19]

Bump for today

[OGDENS SUGAR BUSH]

So I picked up a shallow well pump and it is rated for 10gpm. Now that will be significantly more than my RO will he processing. My procon is rated for 4gpm but when it’s pressurized and recirculated I will be putting out like .5gpm. My well pump has a pressure switch and I don’t want it to cycle repeatedly. How have people dealt with this scenario? Do I recirc the feed pump back to the tank to allow it to flow and to eliminate cycling? Do I just turn the pressure switch way down or override it?

The reason I went with this pump as I plan to expand to a 4x40 or in the next year or 2 so I wouldn’t have to buy another feed pump then. 20717

When you wire up the pump by pass the pressure switch

[Bmeehan19]

Thank you for your help.