[EandM]

Just changed the resin in both my DI Units. After 2nd tank (400l already made at 0 tds) it's now producing DI Water at 4 tds. Had this last time (first half of same bag of resin) with TDS at 4 for 2 months then rapidly climbed to 46.

How is this possible? For the last 5 years of water production resin starts at 0 tds then gradually creeps up. How can it possibly settle at 4 tds?

Inaccurate TDS meter, dodgy resin or just weirdness?

Any suggestions or ideas welcome.

[Nick Wareham]

Are you sure you got the right type if resin? Where did you get it?

You need Tulsion 115 (Not 111)
Or if using purolite, its MB400

Some types of resin, usually cheaper, is not as strong as these types, and doesn't bring the TDS to zero.

Annoying though it may be, water at 4 TDS will probably still be ok to use and I doubt it would leave spots.

[EandM]

Thanks Nick. I'm running it through a 2nd DI Unit and it comes out at 0 tds without any problem and lasts a couple of months in normal use. I get my resin from Cedric at Cleaning Spot, have done for nearly 6 years and no problems to date, except this one. Seems to last ok just not getting 0 TDS. Another window cleaner did have a similar problem last year, different supplier, and we looked at all the usual suspects but never traced the source of the problem. Was just hoping that someone on here had been affected and found the answer.

[Nick Wareham]

I just looked on the cleaningspot site, and saw what they are calling "cedilite" which I would guess is from cedric > cedillite.

I would be very suspicious of a bag of resin that you don't know what brand it is, even if they are claiming to be "equivalent" to MBA400 etc. I mean, how can we ever know that it is what it claims to be? Or even mixed with inferior resin?

I'd send it back and demand it be replaced with a bag of tulsion or purolite, that is still in its original packaging so that you can see what exactly it is.

[Craig Trevain]

There is nothing wrong with cedelite, works fantastic. dont be suspicious.

[alanwilson]

how quickly are you putting it through the resin?  How big are the di vessels?  Some resins will di quicker than others, while the slower resins will di the same volume of water they just need to have the water passed through slowly.