Delivery Pump for RO

[Khazmodain]

Not completely reef related since this is a different RO system than my aquarium system... but figured this group may be able to help. I have a BRS RO system for drinking water (no DI on this one). It's in my basement and feeds a faucet in the basement and a refrigerator in the basement. I recently extended it to the upstairs refrigerator and the pressure leaves a bit to be desired. So I'm considering adding a delivery pump but am fairly confused as to where it should be placed in the system. I already have a permeate pump.. would that come out or does that get left alone? Here's my lovely attempt to illustrate the layout...
To clarify, 1,2,3 is just the order of the prefilters. CV is check valve, ASOV is auto shutoff valve.

Hopefully this makes sense to someone who can help!

Thanks in advance!

 

[griss]

A couple of questions to clarify. Side note: the diagram is

Is your concern about the pressure across the membrane (the pressure gauge on the membrane housing) or that water reaching the upstairs fridge?

Is the reservoir and pressure tank? If so, and the issue is flow to the newly hooked up fridge, the pressure issue could be because the line to the fridge is before the pressure tank.

Is the, "Perm Pump" in your diagram an RO Booster pump? I'm also a bit confused why the output of the Perm Pump goes to both the ASOV and the RO membrane.

Typically, the booster pump should come before the RO membrane. (Ignore the DI in the diagram below since you're not using one on this system).

 

[Khazmodain]

To clarify, I don't need the PSI boosted going into the membrane, the supply water pressure is fine. The pressure going out of the reservoir/pressure tank is fine in the basement, but it's too low once it reaches the upper level. The perm pump = permeate pump which just uses hydrostatic pressure from the waste line to boost the delivery from the RO membrane into the storage tank. The line to the fridge is after the pressure tank. The faucet in the basement is before the pressure tank but it gets plenty of pressure (direction shouldn't matter on the tank since there isn't really connected in-line).

If I had to guess, I would think what I want is a demand pump that would sit between the storage tank and the taste filter.

 

[griss]

Gotcha. Completely forgot about permeate pumps as I’ve never used/needed one. I’m not sure what to suggest.

@kharmaguru any ideas?

 

[kharmaguru]

Upgrading to 3/8 tubing/fittings would most likely do the job.

 

[five.five-six]

RO booster pump may be what you are looking for. It has a pressure switch to turn on only when the ice maker is filling.