[johnm]

my tds is going up aft 2 weeks with new resin is this normal

[macmac]

depends how hard your tap water is & how much pure water you've used in two weeks.

tony

[johnm]

maybe 2000 liters

[chris@c.m.s]

how large is your di vessel and what size and type of Ro are you using?
 

[macmac]

& what about the tap water?? tds?

[RO-Sheen]

I had this problem a while ago where my TDs was going up to 14ppm!!! I have an Ionics Pro5 so changed my resin but within about 10 mins the TDS was going back up to 14ppm.
I checked the tds of the RO'd water and found it to be about 14ppm whereas before it used to read 8ppm.
I then flushed the RO for a good hour with tap water and this brought it back to 8ppm. After the RO'd water goes through the DI it takes it down to 5ppm.
I know alot of w/c's here wouldnt work with that but it still leaves the windows spotless. In fact, I would happily work upto to 8ppm (but would still go back to check my work when the windows have dried)
Once it gets to 8ppm I will then change my resin as it clearly would not be working anymore.

[Ian_Giles]

Once your R/O water has gone through your resin it should read 0.000 ppm.

you must have a problem with your resin!

There is a formula for working out how much pure water your resin will give you per litre of resin used and the TDS of the water going into the resin....but I can't remember what it is

Ian

[Seers]

Hi,

My pressure has dropped down to around 35psi going into my R/O when usually it's around 60 to 70 psi. Can anyone tell me why? There is no problem with water pressure from tap, I think maybe part of the R/O or filters may have a problem.

The pressure adjuster on the R/O (for flushing etc) makes no difference on psi guage now either. The R/O is a 600gpd.

As a result I am only getting a tiny trickle of pure water going into my IBC. 

Cheers,

Huw

[Paul Coleman]

Once your R/O water has gone through your resin it should read 0.000 ppm.

you must have a problem with your resin!

There is a formula for working out how much pure water your resin will give you per litre of resin used and the TDS of the water going into the resin....but I can't remember what it is

Ian

500,000 (half a million) divided by TDS = no of litres per 25 kilo bag of resin.  It can vary a fair bit though I think but that's a good starting place.
Therefore, if TDS is 250 (a reasonable average for hard water), that would give about 2,000 litres per 25 kilo bag.

[NWH]

Some RO,s when new come with a solution in them that protects people from disease this is normally done if they have been shipped from abroad,you could think that you have a bad batch of resin but you might find if it`s a new RO and it`s been washed in that solution it could be that causing the problem.It normally takes half a bag before it sorts itself out so i`ve been told.

[JM123]

TDS should never rise quickly if its new - if it does then its more than likely a bad batch of resin that has dried out.

[DASERVICES]

John,

As you live in Scotland your resin in your DI vessel should last and as you use Purolite for at least a month and a bit. One problem that you could have is your tubing in your DI vessel is bowed, pull it out from the DI head and if it is not round then your resin will have been contaminated.

If you look after your resin a quality resin should last at least 4 mnths for a 25 l bag.

Doug

[johnm]

thanks still at 1