[combat1]

Hi Guys, my RO pressure is not good, ref previous posts.
Changed everything, filters, membranes the lot.
I have an on/off valve on the waste pipe and I’ve noticed that if I shut it half off the pressure rises by about 20 psi. Which produces water faster.  At the low psi I cant make enough in time and am running to Spotless all the time.
My question is, would doing this damage the RO system, membranes etc?
Thanks

[nathankaye]

Why not run a booster?

[combat1]

Thanks Nathan, got a booster but pressure still 40/50psi. Goes up to 60/70 when waste valve closed half way. Going to try replacing the flow restrictor, which was changed along with the filters and membranes, might be a naughty one?

[Spruce]

Thanks Nathan, got a booster but pressure still 40/50psi. Goes up to 60/70 when waste valve closed half way. Going to try replacing the flow restrictor, which was changed along with the filters and membranes, might be a naughty one?

With the valve half closed, what is your pure to waste ratio?

Easy to check by filling 2 x 25 liter containers side by side, one pure and the other waste.  Even 2 small plastic milk containers the same size would also suffice.

If you are in flush mode the r/o produces lots of waste and very little pure so I would think that you were sending too much water to waste with a 20psi pressure rise restricting the waste more. With the half closed valve, what is your pure tds you are producing compared to the tds of your tap water?


.

[Ooooooog]

Try running 1:1 and see what the pressure is like.

[Spruce]

Try running 1:1 and see what the pressure is like.

I think Combat's water area is quite hard.

[combat1]

thanks all, I’ll measure the ratio later. The water here is quite hard, around 300 I think.
One thing I did notice was that the new sediment filter soon became brown, have changed it again. Maybe water quality not too good.

[combat1]

When the waste valve is just over halfway closed the ratio is 1 of pure to 1.4 of waste. Tds coming out at 0.

[Seers]

Hi,

Weve just installed a booster pump and our pure water production rate has at least doubled.

We had a low pressure of about 30psi previously.

Should have done it a long time ago.

Kind Regards,

Huw

[Seers]

Hi,

Forgot to say our tap water is 170 and after the R/O TDS was 18, now with booster after R/O  TDS reading is 3.

[combat1]

Booster pump certainly makes a huge difference, before the Christmas break my system was working so well, oh well! Off to Spotless early tomorrow and should be able to make enough for Friday.

[Ooooooog]

I’d consider changing the sediment filter before it’s brown!

[combat1]

Usually does 3/4 months, i’ve changed this one at 2.

[Don Kee]

Something is definitley wrong, my mains pressure is about 30psi and ingoing TDS is about 330ppm.

Booster takes it up to 80psi and RO produces under 10.

What type of RO do you have?

[combat1]

300 litre 2 membranes.
I used to be at 80psi as well.
System is inflow to sediment filter, carbon and carbon block then through booster pump to RO then through resin to storage tank.
As pressure after filters is low it must? Be between inflow and pump?

[nathankaye]

I use 3 x 150ltr membranes RO system.
Water comes in at just under 300tds and hits my sediment filter and then through the fibredyne (however its spelt) and then the booster which takes it from 30 or 40 psi up to 70 psi then through the membranes. It comes out at either 006 or 009 (not checked for a while) and straight into my ibc tank. I dont bother with resin and havent done so for quite a while now.


So something is a miss.
Have you back flushed it?

[combat1]

Yes mate back flushed. Do it before and after each batch.
Have closed the waste valve down to push the pressure up to 70, so producing at the old level now.
Sod it! Fed up of farting around with it. Will run it like this for a couple of weeks and then have another pop.
Thanks all.