[focuscoleraine]

Hi guys

I would be grateful for some help.  I have been WFP from May this year, i am using a Pure freedom 300 GPD RO unit.  Water from my tap is 160ppm.  The system was working well until this week when the reading went to 002ppm.  I bought 5kg of Tulsion MB115 from PureFreedom and changed the resin.

The reading was 000 for a couple of days then went to 002-003, i changed it again and it was ok for a few days and then the reading went 003-005.  I checked the reading from membrane before DI and it was 002.  I have i bought dud resin or am i doing something wrong when changing the resin??

Thanks for any advice.
Des.

[CRYSTAL1984]

change the set pre filters

[andyM]

It all depends on how much pure water you are producing really which will determine how long the resin will last.
If the RO was new in May this year as I think you have said it shouldn't be the pre-filters.
Are you using a DI canister or DI vessel for your resin?
A larger vessel will last longer between re-fills.
I always disconnect my DI when I first start running the RO and keep it running until the PPM reading settles down. Otherwise it can remain quite high for a while when you first start running it and this could shorten you resin life.
Might be worth checking it.

[andyM]

It might be that you have a dodgy batch of resin but quite unlikely.
You can still clean windows witha reading of 003ppm without any problems.

[john tomkins]

change the set pre filters

Incorrect advise ..... he's already said the reading after membranes is only 2 so that side is fine.

As AJM said depends how much water you are producing and what size resin container you use.

Are you also removing tube between membranes and resin before you turn the RO system on, as initially TDS mfrom membranes will be very high and will eat up your resin very quickly.

[MoemGorod]

I bought 5kg of Tulsion MB115 ...

Hi Des.

The resin is always measures in liters (gallons). Of course it has the weight (25ltr bag - 14kg approx.), but such as it fills the vessels (cans) the suppliers sale it in liters.

For DI water counting you can use the TDS calculator - http://cleantech.co.uk/tdscalc.htm or formula 20000x5ltr/002ppm=50,000ltr of DI water.

So its, indeed, unreal for you (for one WFP operator) to use this 50,000ltr in couple of days. Even if the DI resin you have bought is not perfect.

It is not rare thing when the users confuse with the out and drain from the RO unit. By my opinion, it is looks like that. Anyway, check your RO-DI connections carefully.

regards,

Vadim

[focuscoleraine]

Hi guys thanks for replying to my post resin problem.The 300gpd ro unit i use has a 10 inch di vessel and i make 250lts per day which suits our needs at present. When it came from Purefreedom the resin was in it.  This lasted from May this year until this week when the reading went to 002.  As I said in the earlier post I put new Purefreedom resin in the vessel and it read 000 for 2 days then went up from 000 to 004.  I changed it again and it was OK for another couple of days then reading went from 000 to 004 again.  The water from the membrane is reading 002 and when I connect up to the di vessel again instead of reading 000 it reads up to 005.  I expected the new resin to last as long as the original resin.  Has anyone got any answers?

Regards

Des

[john tomkins]

Something aint right here....

You said in the 1st post that reading from your membranes before DI is 002,
then you said the reading after DI went to up to 005

If all the resin is depleted then you'll just get 002 running straight through it.

Are you sure your TDS meter ain't dodgy?