You know, now that you mentioned it. I do remember having issues with Orings as well. I cant remember much problems with these system though (I worked with a very small units - a few 60 gal day, also with a 2000 l/day, and also a 350 ton a day unit) didn't really have much problems that I can recall with most of them. But that was mostly because I wasn't directly responsible for it, and it was kinda of a "scary piece of equipment" apparently, so it was only used when really needed. But when it was running I did not experience many problems.
I don't remember much, but I though we were getting much lower salinity readings, something like 50 ppm or the likes. 300 sounds still a bit high. And yes I do remember cursing the manuals and their lack of clear explanations. Mmmm. strange how these problems keeps on living in this day and age.
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