How to increase flow

[Bricklayer]

I've got my RO plumbed the following way

Supply pump (1.5 hp 1000 gph)
1" ID suction line (gravity fed from tank)
3/4" ID outlet from supply pump to 10" filter housing
3/4" outlet of filter housing to hp pump inlet

Hp pump ( 1 hp Weber Webtrol multistage booster)
3/4 ID feed from filter housing
1" outlet tee bushed down to 1/2" Npt
3/8" high pressure line feeding membrane

Supply pump will push 50 PSI but only 5 gpm across membranes by itself
If I run booster pump as well I go up over 160 PSI but 7.5 gpm. Recirc valve open a crack
With recirc wide open and concentrate needle valve wide open the pressure will drop a bit maybe to 145 psi or so . If I close the recirc the pressure climbs to almost 200 psi

Unit works great while concentrating. No problem at all
It's getting the flow up and pressure down for cleaning and rinsing is what I'm trying to do


Will increasing my ID of tubing help?
Maybe a 1" ID tube from pump through the filter to the supply of the hp pump?

Increase the high pressure hose to feed membrane to 3/4" or 1/2" ID
Increase the size of the concentrate out line on the membrane to 1/2" ID?

Both my needle valves are 1/2" needles valves

Concentrate out lines and permeate out lines are 1/2" OD tubing

[Super Sapper]

Your pressure is created on your concentrate line. If your concentrate valve is wide open and you are still getting higher pressures it would be in the concentrate valve and line size creating back pressure. If you have lower pressures and low flow it would be in the lines feeding the membrane. I am assuming that your pressure gauge is downstream of your membrane as your pressure is caused by restricting the downstream side.

[Bricklayer]

My pressure gauge line for high pressure comes off the tee where my hp pump feeds the membrane. So it shows pressure being applied to membrane from pump.

[Super Sapper]

Try to measure you pressure between your membrane and your concentrate valve. This will give you your loss across the membrane. It should not loose much unless there is a restriction inside the membrane itself. It should be a straight shot through the membrane with the concentrate valve open but you are restricted somewhere downstream of your pressure gauge. I do have an RO and it has been awhile since I troubleshot them so if you can see what other people are getting for pressure that would help.

[Bricklayer]

The membrane I have in my RO right now is a used xle 4040. So maybe that's the problem. I've been using it for testing and making permeate. Have acid washed it and soap washed it. Rinsed it. Figured it was good to go. It's hard to base other people's flow Estes unless the machines are the same. Mine is basically a home build so I had no idea what types of flows I was supposed to be getting. I have a brand new MES membrane that I haven't even taken out of the box yet. I'll put that in and see if it helps. Was planning on putting it in right before I got some sap so I didn't have to worry about storing it before I even used it. I've got a tank full of permeate so I can run it through the new membrane. Will have to store it or maybe just fill RO with permeate and leave it till I get some sap.

[Super Sapper]

You could run it without a membrane to see if it is still restricted. Another place I thought of could be your concentrate flow meter. You will be limited in flow to whatever the high end is on the flow meter.

[Bricklayer]

You could run it without a membrane to see if it is still restricted. Another place I thought of could be your concentrate flow meter. You will be limited in flow to whatever the high end is on the flow meter.If I take membrane out and run RO. Do I just add both permeate and concentrate flows together to get total flow? Because I will be getting equal flow through both lines with no membrane installed.

[Super Sapper]

I would only run the concentrate to see if the system can handle the flow without the higher pressures. If it runs this way at lower pressure then I would say that the restriction is in the membrane but that would be unlikely unless there is something stuck in there. A plugged membrane would decrease the permeate flow but would decrease pressure as you opened your concentrate valve. If the pressures remain higher then your system has a restriction. possible the concentrate flow meter size.

[Bricklayer]

just ran it with no membrane, there's no way to just run the concentrate. Both Flowmeters max out and flow out of both Without membrane in there is nothing to separate them. Good way of cleaning out the RO though. Dosnt seem like there's any restriction doing it this way. My system pressure matched my filter inlet pressure so no restrictions in system. Must be membrane.