[Tom ling]

Hi guys, on a 10 inch R/o housing there are 3 in/out connections
One in the lid and two and the bottom is there a set rule on which has to be water in
Pure out and waste out?
Only reason I ask, is after seeing a couple of peoples RO filters on here they are wired up differently to mine, iv got my water splitting from my pre filters and going into the lid and a pure and waste at bottom, but my pure freedom 450 system seems to have a waste water connecting two filters at the bottom but the pure just comes out and into a T connector. The waste just doesn't seem right, Anybody shed any light plz? Many thanks tom.

[Don Kee]

Some r.o's are set up the the previous membranes waste feeds the next membrane (in - line)

Some r.o's split after the pre filters, with t pieces separating the feed  so that each membrane has the same in going tds (my preference) with the waste from each going into one waste pipe, and all the pure from each collecting together (in parallel)

Is this what you mean?

[Tom ling]

Some r.o's are set up the the previous membranes waste feeds the next membrane (in - line)

Some r.o's split after the pre filters, with t pieces separating the feed  so that each membrane has the same in going tds (my preference) with the waste from each going into one waste pipe, and all the pure from each collecting together (in parallel)

Is this what you mean?
[/quote
Thank you for your response that's exactly what I mean.
Mine was the first but I'm changing it to the second,
so if I carry on with the pre filter water being split into to 3 R/O filters then simply gather the pure water into the same  pipe and put the waste into the same pipe with the flush valve on.
I don't understand the first way as surly the filters would wear out faster and not evenly?

[Don Kee]

Yep, exactly how you've said

I dont really know why you'd put them in line if i'm honest, it may have a slightly less waste output but if you offset that with 2membranes wearing out quicker it doesn't save much imo....

[Spruce]

Some r.o's are set up the the previous membranes waste feeds the next membrane (in - line)

Some r.o's split after the pre filters, with t pieces separating the feed  so that each membrane has the same in going tds (my preference) with the waste from each going into one waste pipe, and all the pure from each collecting together (in parallel)

Is this what you mean?

They set a mates r/o up so the first 2 membrane housings are connected as you described and the third has the 2 wastes as its inlet with a single waste then going to the drain and the pure joining the first 2.

[Don Kee]

Some r.o's are set up the the previous membranes waste feeds the next membrane (in - line)

Some r.o's split after the pre filters, with t pieces separating the feed  so that each membrane has the same in going tds (my preference) with the waste from each going into one waste pipe, and all the pure from each collecting together (in parallel)

Is this what you mean?

They set a mates r/o up so the first 2 membrane housings are connected as you described and the third has the 2 wastes as its inlet with a single waste then going to the drain and the pure joining the first 2.

Any idea why its set like that?(i.e what are the benefits?)
Wont the 3rd membrane need changing alot more frequently than the other 2?

[Tom ling]

This is why I love this site lol. I'm leaning all the time :-) it's daft but I really couldn't get my head around it

[Spruce]

Some r.o's are set up the the previous membranes waste feeds the next membrane (in - line)

Some r.o's split after the pre filters, with t pieces separating the feed  so that each membrane has the same in going tds (my preference) with the waste from each going into one waste pipe, and all the pure from each collecting together (in parallel)

Is this what you mean?

They set a mates r/o up so the first 2 membrane housings are connected as you described and the third has the 2 wastes as its inlet with a single waste then going to the drain and the pure joining the first 2.

Any idea why its set like that?(i.e what are the benefits?)
Wont the 3rd membrane need changing alot more frequently than the other 2?

I don't know why it was setup like that Don.

The 450GPD one that I had was setup as you described with each membrane getting the same water TDS from the prefilters (in parallel.)

Connecting them inline (in series) is supposed to save water by reducing waste but it will increasing tax each subsequent membrane as the waste has a higher tds input as you quite rightly stated.

I sometimes wonder if the reason why they also put them in series is to save on JG tees to either make the r/o cheaper or so they can make more profit.
Maybe they are also counting on you replacing all 3 membranes when the last one in line fails first  - this would certainly be the right procedure anyway.

If my memory serves me, I think that all 3 variants are illustrated on RoMan site; or they were at one time.

[Ian Lancaster]

This is why I love this site lol. I'm leaning all the time :-) it's daft but I really couldn't get my head around it

Maybe you're leaning the wrong way?

[Frankybadboy]

page 6

http://www.ro-man.com/instructions/RO-MAN%20Reverse%20Osmosis%20manual%20for%20200%20and%20300%20GPD%20systems.pdf