Needle valves

[iby]

I'm wondering what you all use for needle valves.

Last year in my RO setup, I bought a cheap 1/2" needle valve, but what I found was the max flow on it was too low, so even when I opened it up fully, I was still seeing 180-220 PSI...
I'm thinking I need a better needle valve that will allow more flow through when it's wide open to allow for better flushing.. I suppose I could also add a gate/ball valve in there to open it wide up...

btw, I'm running a 5 series procon, so max PSI is 250 and flow rate is 5 GPM. All schedule 40 PVC 1/2"

any recommendations would be appreciated, especially if they were budget conscientious recommendations :)

[Chickenman]

Not sure of your set-up, but could you plumb in a tee above and below the needle valve with a ball valve in between the tee's to work as a by-pass when you need full flow and not touch the needle valve at all? Just a thought.

[OGDENS SUGAR BUSH]

https://www.freshwatersystems.com/products/hydronix-adjustable-panel-mount-flowmeter?variant=13250147319851

or you could do this

[Clinkis]

I have the same issue with my current RO. Had to plumb in a bypass valve for flushing and washing.

[Bricklayer]

2071020710I just replaced my needle valve on my RO. I was having the same issue.
In the picture attached you can see how small the port is inside the valve( $17 EBay) This was causing my pressures to be at 150 psi with the valve wide open. Last year I plumbed a bypass controlled with a ball valve and it fixed this problem.
I bought a proper needle valve from freshwatersystems.com ($69)and it is full flow. I still have the bypass. And when washing I open it up as well for more flow.
It’s worth paying good money for a needle valve it’s pretty important.

[iby]

I took the advice of a bypass. This year I built a manifold with a ball valve, a gate valve and a needle valve. Now I can flush at zero psi and have complete control of the pressure. Very happy with the suggestion to do that. :)