[Fieldsy]

Whilst I was running my little 100gpd through 2x 700ml DI units, i was capable of a tds of 000 from 350main, it has significantly got higher, so I decided to change and upgrade to 200gpd (to produce more), and bought some tulsion resin to replace in the two DI units.
Now, the tds is stable at 002, and won't go below. Am I expecting too much to get 000 from a 200gpd unit with only 2x700ml, and is 002 the best I can expect from this set up???

The original 100gpd membrane and filters are only about 6-7 weeks old. When should they be changed??

What I'm trying to say is, even if I changed the filters (which I wouldn't assume is due yet), is it still possible that the tds will stay at 002, because of twice the amount of water going through the two DI's

thanks

Fieldsy

[d s windowcleaning]

your tds will go down to 000 did you disconnect your di when you fitted the upgrade kit and run water through it for a while i normally do 25 ltrs of water when fitting a new membrane . then re connect the di .

[Fieldsy]

its been running for about 4 hours and still at 002, so that looks like where its going to stay 

[DanielUK]

350 going into the RO should come out at about 007.  A cupful of resin will get that down to 0.

Disconnect the resin part, and take a TDS reading from the output of the RO.

Also, the more membranes you add the higher the water pressure needs to be.  What pressure are you getting?

[John Walker]

If you ran the system with the new membrane straight through the resin then the high initial contam might have used up the resin.

I always bypass the resin when flushing a new membrane as I has similar to your problem once.

[Fieldsy]

Thanks Dan, just checked water from RO and its 025 ??

@John, when I initially connected the membrane, I ran the water for about 15-20 litres and got a tds of 011, so suspected the resin,so the membrane should have had a good flush. I've now changed the resin and still getting 002


thanks
Fieldsy.

[Fieldsy]

so does anyone think that 25 from the RO is high ?? , could it be a filter change??

[d s windowcleaning]

so does anyone think that 25 from the RO is high ?? , could it be a filter change??

i dont think you need new filters mate , ive just checked mine and its 23 i only put new filters and membranes in last week my tap tds is 370 .

[Fieldsy]

Hi Dave,

well to cover all options, I replaced the filters and bugger me the tds is still 002 after running about 25 litres of pure : :.

The resin is brand new, that only leaves the membranes.......and they can't be knackered yet surely??

One thing I have noticed, the second DI in sequence is taking bloody ages to fill once its passed through the first. The first fills up in no time, the second takes a good half hour to fill up???. I know this wouldn't have an effect on the tds....but weird why its taking so long.................it filled up in no time when I originally set the system up. Since changing the resin, the second takes ages??

cheers

Fieldsy

[elite mike]

you need a water pressure of around 65 psi or more to get the results you want

[Fieldsy]

I have an 85psi booster pump, I thought that would be sufficient???

[steven ainger]

you need a water pressure of around 65 psi or more to get the results you want

mikes right,
 my ro-man 200gpd ro is over 2 years old, same membranes, change the filters every 6 mnths,
my tds is around 600 and the ro will still knock that down to 8, but i use a booster pump at 85 psi

[elite mike]

I have an 85psi booster pump, I thought that would be sufficient???

should be more than enough there fieldsy

cannot understand what else could be the prob really  

try just using the first di and see what happens

[steven ainger]

are they inferior membranes, where did you buy them from

[paul saunders]

How do you have it set up? Do you have any pictures?

[Fieldsy]

membranes/system etc.... were bought from vyair, and it was running fine before introducing the 2nd 100gpd.


I'll upload a pic 

[elite mike]

looking forward to pics 

mind you a tds of 2 would not worry me fieldsy   

dont lose any sleep over it

not heard of vyair before, good prices

regards

mike

[Fieldsy]

notice how the second di is still not full and thats been running for about 1.5 hours

[elite mike]

hmmm not sure , ime thinking air lock

but not sure,will look at mine 2 moro and get back to you

wheres andrew mcann when you want him

[Fieldsy]

Hi Mike,

Would an air lock cause the problem, and if so whats the best way to release it. I filled the di cannisters with resin about 2 inches from the top. Should they have been packed to the brim??

thanks for all the advice.

Fieldsy