Ro Unit Maintenance.

[john.o]

I am looking for some advice peeps, on the maintenance that needs to be carried out on my RO unit

after having a operation I have been unable to do the regular maintenance on my tank myself, and just recently I have noticed a difference in the appearance of my corals so after doing some tests on my tank and finding some alarming readings . I have traced the problem back to my RO unit, the readings where 62ppm and now it just seems no matter what I do with my RO unit I cannot get my readings down below 26 ppm {ppm in flow 189} I have changed the 5 micron Sediment filter and the Coconut Carbon Filter + the DI resin as I normally do every 6 months {or sooner if the TDS readings go up} the unit is 14 months old now and the only things I have not changed is the Membrane filter {Do you need to replace this filter? No info in the instructions about changing it}
also the RO man inline tds meter is the original. Do these have a shelf life? Dose this need replaced also?

 

[seffieuk]

How you doing John? How did the op go?

Yes you do have to change the membrane and they are usually quite expensive

Seffie x

 

[john.o]

Hi seffie .
Yep the op went ok thanks
It was suppose to be just keyhole but I guess once they started it was worse than first expected. so they had to open me up a little more {4 inch more } and do a open mesh hernia repair, it was painful for a few days after but it’s all good and I feel much better now and well on the road to recovery, I still can’t lift any think too heavy for a few more weeks yet but me good lady wife’s helping me out as much as she can with the tank .so again it’s all good I guess, or it will be once I sort this dam RO unit out, umm so you do have to change the membrane!! How often are you suppose to replace it? Just for future reference I am guessing more often than every 14 months and what about the TDS meter is that same? {regular replacements required}

 

[ben1987]

a good membrane lasts a fair while mate. when was the last time you replaced DI and the pods? do this first then check TDS as it would be a lot cheaper!

 

[john.o]

a good membrane lasts a fair while mate. when was the last time you replaced DI and the pods? do this first then check TDS as it would be a lot cheaper!

Hi ben
Thanks for the reply
I have just changed the 5 micron Sediment filter and the Coconut Carbon Filter + the DI resin yesterday {the 3rd time I have replaced in the 14 month I have had the RO unit} the unit still has the original membrane in it, its 14 months old now also the Roman inline TDS meter is the original one .

edit to add....
I have ran the unit for 2hrs but still no change in the tds 26ppm
I am thinking a new membrane and or a TDS meter?

 

[seffieuk]

I didnt know you had to replace the TDS meter?

Seffie x

 

[john.o]

I didnt know you had to replace the TDS meter?

Seffie x

ok it looks like I have been over thinking the inline unit ,

I know the pens can be recalibrated so I thought that perhaps the in line units had a shelf life on them due to the probes getting clogged up with lime scale ect. But after doing a little bit of google in it seems that the unit I have, has a advanced microprocessor fitted to it that is calibrated at the factory and Recalibration is not necessary and when you think about it the probe that gives the reading that I am interested in {flow out} is after all the pods so there should be no nasty’s that get to it to fouled it up so it’s got to be the membrane that’s at fault and not the TDS giving false readings

 

[rabbut]

Oh, it could still be the TDS meter. they are electronic, a small knock will make them drift IME I don't like any meter you can't calibrate. If an electronic meter isn't calibrated, it's as accurate as pulling random numbers out of mid air for your test result

However... It probably hasn't drifted out by 26ppm in a few weeks

Try a prolonged membrane flush - 1 hour or more, and then go back into use mode for an hour or two - see what the TDS stabilises out at then Failing that, it's new membrane time

 

[john.o]

Problem sorted
Thank for all your help peeps

1st
Changed the DI resin to start with
RESULT very little to no change which I was very surprised about because the resin was as black as the night
2nd
Changed the 5 micron Sediment filter and the Coconut Carbon Filter
RESULT a change of 9 ppm in the reading but still not good enough for me
3rd replaced the membrane {omg £29 }
RESULT again a small change in the TDS reading of 2ppm but still not what I was expecting with all brand new filters and resin I was hoping for a reading of zero {now at 15ppm}
4 th go out and buy a new TDS pen just in case I am getting a false reading from the inline unit
RESULT same reading from the pen as from the inline unit ummm!!!
5th go sit down in the huff and think about it a little.
RESULT :stupid: what a idiot when I took the DI resin unit off I replaced it the wrong way around which is not a problem in its self, the problem is the out flow probe is connected to the DI unit so it was replaced in the wrong part of flow I.E before the water had completed it cycle through the filter. So with this tern round and the probe in the correct place the readings are now zero.

So after all that it was properly just the DI resin that needed changed anyhow £79 later all sorted and I now have a new toy as well {my TDS pen }

 

[seffieuk]

Oh you donut, that is just the sort of thing I would do

Seffie x

 

[john.o]

Yep feel like a complete idiot

 

[rabbut]

15ppm out of the membrane is still very high really. Unless your feed TDS is about 1500ppm - 1000ppm above the legal maximum

 

[john.o]

15ppm out of the membrane is still very high really. Unless your feed TDS is about 1500ppm - 1000ppm above the legal maximum

Really
Ok well there is defiantly some think still wrong with this unit!
When I first got the unit I immediately noticed that the diagram for the built in flush was wrong



Basically they had it the wrong way round when the tap was open it said PRODUCTION and when closed FLUSH / I emailed the company about it and they gave me a load of free filter cartridges and some DI resin as way of compensate
and thinking back now I remember when I first bought this unit I got it a little cheaper than the marked price as there was no packaging {display model I was told }
so I am now thinking perhaps the unit has been plumed up wrong from day one .

Here is a diagram of how my unit runs....

189 ppm Flow in throw the membranes down into the pods {my pods are the other way round 5 micron 1st then carbon} then up into DI pod and clean water zero TDS out

I will try to get a pic of my actual unit later on {it’s a little difficult to get a good shot as it’s under the sink and I cannot get it in focus with the camera }

 

[seffieuk]

I think Trod might have the same one, I will text her

Seffie x

 

[john.o]

O thanks seffie