[JTHRC]

I have connected a di unit to my RO filling my IBC tank, in order to get 000 water for the jerry cans on board.
It was reading 000 for about 2 weeks but has now shot up to 006 so i have to refill resin again

Just wondering whether if I used two RO'S, would that work and be better??

My RO on its own currently only gets it down to about 035.

Any help would be appreciated.

Thanks

[Simon_King]

Putting a booster pump before the RO should bring the tds down before the DI.

[JTHRC]

Seriously?

I thought that the Merlins didnt get as good a quality beacause they are too fast at letting the water through and therefore quality is worse??

Can u explain why that will bring the tds down please mate?

[windowwashers]

Seriously?

I thought that the Merlins didnt get as good a quality beacause they are too fast at letting the water through and therefore quality is worse??

Can u explain why that will bring the tds down please mate?

It puts more pressure on the membrane giving a lower tds out, I would also have 2 di vessals as 006 resin still has life

if ro is 35 out di can go upto 35 before needing to chuck away while the second stays at 000. when second starts to rise change resin in first and swop them over it really does make a difference onm your resin use.

Ian

[Mr H]

Merlins need a water preasure of between 40 and 80 psi with optimum being between 60 and 70.
www.ro-man.com/shop/product_info.php/cPath/22_94/products_id/130
As Window Washers said it needs the preasure to push the water through the membrane.
Using 2 RO systems would reduce the TDS but you would waste so much water. Even if you had a very water friendly RO at say 1 - 1 you would need 4L going in to get 1 lt of 0 out giveing you 3L of water down the drain.
Getting the preasure right will help in getting the TDS down and if its below 40 then that quite soft so worth DIing rather than second RO.

Regards
Mr H

[michael papworth]

Seriously?

I thought that the Merlins didnt get as good a quality beacause they are too fast at letting the water through and therefore quality is worse??

Can u explain why that will bring the tds down please mate?

I puts more pressure on the membrane givingh a lower tds out, I would also have 2 di vessals as 006 resin still has life

if ro is 35 out di can go upto 35 before needing to chuck away while the second stays at 000. when second starts to rise change resin in first and swop them over it really does make a difference onm your resin use.

Ian

Spot on.

Using two ROs in tandem wouldn't work.

RO units depend on pressure for their operation. The higher the pressure (within their rating) the better they work.

High pressure => lower tds and lower reject water.

If you use 2 x RO units in tandem, you'll get lower pressure across each (since the mains pressure will be halved for each one) and hence higher tds and MUCH MORE waste water.

So, either get a booster pump or use 2 x DI units in tandem as windowwashers says.

[JTHRC]

Ok, thanks alot for all your help fellas

[STEVE-UK]

do you have a water softner before your pre filters?

i have a kenetico 2020c fitted ,it bought tds reading down from 35 to 13

water from tap is 272

[Londoner]

Just a question. How big is the DI unit?

[STEVE-UK]

they range in size  from 1 - 4 foot tall,the bigger it is they longer the resin lasts as there is more of it