RO,DI Setup question

[shanemorgan]

Hi there all
I have got maybe a problem with my new RO system i am not realy that experianced enough to truely know mind. I have got a 4 stage RO MAN system which i can not get the TDS to run below 3 ever. What i have done so far is change out all the fillters and replace the DI resin with brand new stuff the plumbing for this runs as follows. Main input straight in the canister micron fillter outputting into the carbon cainster fillter outputting into the membrane fillter outputting into the DI resin canister and then outputting as RO water. My input TDS is 65 and the output is 3-5 TDS it should be running at 0 TDS and i cant understand why i have checked this with both inline TDS meter and also handheld TDS pen the pen type tester has been callibrated with proper solution so i know this is accurate the inline one i tried to calibrate with solution but it didnt realy like being adjusted its brand new and i think there maybe a fault with it but i trust the pen one 100% as i tested it on LFS water.
Any help would be awsome
Thanks in advance
Shane

 

[pmrossetti]

with an input of 65 you should get 0 easily.is it a quality membrane?

 

[shanemorgan]

Hi there
Thanks for the reply the membrane is one from my LFS i took the old one out of the holder and took it along with me for him to match up so as far as i am aware that is what he did. Since i have had it it has never run dry or anything like that. I bought a brand new RO 3 stage setup off the internet its got everything but not the DI stage and that is giving me a TDS 3 output also but i would expect that to be the case as its not got the DI stage i am going to put this through the DI stage of my RO MAN tonight and see if that comes down to 0 TDS if so then that is highlighting a problem with another part of the RO MAN setup. Can anyone confirm that the plumbing is correct ?
Thanks in advance
Shane

 

[pmrossetti]

Hi there
Thanks for the reply the membrane is one from my LFS i took the old one out of the holder and took it along with me for him to match up so as far as i am aware that is what he did. Since i have had it it has never run dry or anything like that. I bought a brand new RO 3 stage setup off the internet its got everything but not the DI stage and that is giving me a TDS 3 output also but i would expect that to be the case as its not got the DI stage i am going to put this through the DI stage of my RO MAN tonight and see if that comes down to 0 TDS if so then that is highlighting a problem with another part of the RO MAN setup. Can anyone confirm that the plumbing is correct ?
Thanks in advance
Shane

Plumbing sounds right. you should be fine now with 3 going to the DI.

 

[jeff@zina.com]

HMy input TDS is 65 and the output is 3-5 TDS

Let it run an hour or two and check again. Sounds like the new DI resin just hasn't kicked in yet.

Jeff

 

[shanemorgan]

Hi all thanks for the info sorry in taking so long to get back to u. The system is sorted out now i plumbed the 3 stage into the DI and the output was TDS 0 straight away so it is looking like the membrane is in fact in need for replacement in the RO MAN system after all. But for now it is working fine as it is and in the future will replace the membrane ( it was sold to me with a new membrane init according to the seller clearly not though)
Thanks for all your help
All the best
Shane