[Simon Mess]

Just replaced the filters and membranes on my r/o system. It is a 400gpd (but uses 2 300gpd membranes?) system with built in pumps. Put the new filters in yesterday, but due to a mix up, the membranes i had ordered were the wrong size (physically as well as output), so had to order the correct sized ones express delivery. Got the new membranes in at about 2.30pm, the unit has been running constantly since then apart from a 30min break. But the water out of the r/o is still up at 35ish ppm, whereas before the water purity started to go downhill, it was coming out between 8-12ppm. I cant think where i might have gone wrong as i changed each filter and membrane in sequence so i wouldnt put the wrong thing in the wrong place, but just to cover all the bases, does anyone have any suggestions?

Thanks in advance

[Dave Willis]

Have you given it a dam good flushing?

[Simon Mess]

I have flushed it with the lever on the system, actually did it yesterday when the old membranes were still in, but i have never been very sure of how long to flush it for, what would you suggest?

[Don Kee]

Check the membranes individual output (disconnect the pure hose from each membrane) and check the tds to see whether its just one or both membranes with an issue

It will come down though mate (if all fitted correctly) it can just take a bit of time while it gets rid of the crap
(I was told to flush for a hour  or 2 before producing pure...)

[Simon Mess]

Check the membranes individual output (disconnect the pure hose from each membrane) and check the tds to see whether its just one or both membranes with an issue

It will come down though mate (if all fitted correctly) it can just take a bit of time while it gets rid of the crap
(I was told to flush for a hour  or 2 before producing pure...)

An hour or 2 to flush?, i didnt realise it would be as long as that!, but cheers for that. No time to do anything about it tonight, i need to get tank full for tomorrow!. Will just have to hope the di resin in the van has enough life left to keep the water pure .

One other thing that might have a bearing. The membranes that were in it were hydratek, but i couldnt get replacements, at least not at short notice, so had to get FCS ones off a place on ebay called 'thewatersite'

[Dave Willis]

The membranes (new ones) come with a protective coating so I've been told which prevents them drying out in storage hence the need to flush them clean before using the water.

[Simon Mess]

The membranes (new ones) come with a protective coating so I've been told which prevents them drying out in storage hence the need to flush them clean before using the water.

They actually came in vacuum sealed plastic, but i will give it a good flush tomorrow and see what happens. Thanks for the responses

[Dave Willis]

I know - one of mine wasn't vacuum sealed properly but I was told the membrane would still be ok to use due to the chemical coating or whatever it is. I think Alex told me that.