Washing Windows

  • Posts: 95
RO Upgrade 'n' stuff...
« on: November 22, 2012, 04:42:49 pm »
Hi all,

I did register with the forums a few years ago, and I read them a lot, but I couldn't remember my old login detail so I've registered again. /wave

I have a question... well actually I have a few.

As I'm working on a pretty tight budget, I upgraded my 2 year old (pumped) 100gpd RO to 200gpd over the weekend. At least I hope I did, does it look right?



My tap water is 205 tds, which is dropping to 43 tds before resin. This seems a bit on the high side to me and I'm wondering if the original membrane needs replacing? It's less than a year old but I'm not satisfied that the unit has been "flushed" enough in its life time. The system has also been allowed to run with the same filters in it for to long while needing to be changed. I think I'm answering my own question but advice is sought

I should have checked the output of the original membrane before the upgrade but mine isn't an engineering mind and I didn't think. I know I can take a step backwards and remove the second membrane but, finally a reason for the red arrow, I didn't have a clue what the function of the item is that I'm pointing to with the red arrow and it required me to unscrew bits. Undoing things when I don't know what they are or what's inside them has historically gone badly, which brings me to my next question.

What's the thing I'm pointing to with my red arrow? Can it be replaced by one of these? Auto Shut off kit http://www.cleaningspot.co.uk/acatalog/200_GPD_RO_Systems_and_spare_parts.html it's the very last product at the bottom of the page.

I produce pure water 24/7 a lot of the time and I'm hoping the upgrade will reduce my waste water per pure water ratio and generally keep down the cost of producing pure 000 tds water. I'm currently capturing water in a 210L container, which is filled and emptied twice a day at the moment. Using the standard 1 litre resin housing for polishing, how often should I need to replace the resin?

MMmm... a wall, ooopsie.

Many thanks in anticipation,

Duncan

Alex Gardiner

  • Posts: 7740
Re: RO Upgrade 'n' stuff...
« Reply #1 on: November 22, 2012, 04:53:35 pm »
Hi Duncan

The item with a red arrow pointing to it is an auto-shut off valve which is exactly the same as the one in the cleaning spot website.

It sounds like you have damaged your membranes by running them with old pre-filters which have not removed the chlorine from the water supply.

With an input of just over 200ppm on a boosted 200gpd system you should be able to achieve an output of about 003-006ppm very easily. On these outputs you would expect your resin canister to last for about 4000 litres before needing replacing.

Washing Windows

  • Posts: 95
Re: RO Upgrade 'n' stuff...
« Reply #2 on: November 22, 2012, 05:21:50 pm »
Hi Alex, thanks for the quick reply.

The item with a red arrow pointing to it is an auto-shut off valve which is exactly the same as the one in the cleaning spot website.

Oh! the one on my system doesn't shut anything off? As I've mentioned, I'm not the mostly mechanically minded but I would like to be able to set my system so that once my container if full it stops producing water completely. Life has a tendency to revolve around my pure water needs atm.

With an input of just over 200ppm on a boosted 200gpd system you should be able to achieve an output of about 003-006ppm very easily. On these outputs you would expect your resin canister to last for about 4000 litres before needing replacing.

WHAT?!! I've never been anywhere near 003-006ppm, even when the system was brand new! I asked this same question of the guy I bought it off new on the telephone and he said I should expect between 012-014ppm from a tds of 186 (when I live round the corner). I replaced the membrane a little under a year ago and I was getting 018ppm. Is there anything else that is likely to be contributing to me having higher figures than you are advising?

Just want to add Alex, great job with what you're doing with the waterfed poles. I have 4 of your poles now, they're great and I love the sill brushes.

Duncan

Alex Gardiner

  • Posts: 7740
Re: RO Upgrade 'n' stuff...
« Reply #3 on: November 22, 2012, 05:47:36 pm »
Glad you like the poles  :)

The shut-off valve on your system (red arrow) should shut the unit off when the float valve shuts-off. Although I do know how well this would work if your system is boosted with a pump.

Upgrading with a second membrane is a great way of increasing output however if the first membrane is 'shot' then it will not cure this.

The first thing to do is to change the pre-filters if you did not already do this before the upgrade as these will protect any new membranes fitted.

What it may be a good idea to do is to run one membrane at a time and see what each one is producing ppm. This will tell you whether the first one has had its day. You may find that you get better production in this case (if the first one is shot), if you just have the newer second membrane running on its own.

Anything else to improve? Perhaps the pump is not giving enough pressure to get a decent output. Do you have any way of measuring pressure before and after the pump?


dd

  • Posts: 2527
Re: RO Upgrade 'n' stuff...
« Reply #4 on: November 22, 2012, 06:25:41 pm »
My tap tds is approx the same as yours - around 200 - and my ro (similar system) produces around 005-006 tds. I do not use a pump but mains pressure is good - around 55 psi.

Alex has made good suggestions. If being used regularly pre-filters should be changed every 4-5 months.

If the unit has been idle for a while and the membrane has dried out this can allow it to break down.

Washing Windows

  • Posts: 95
Re: RO Upgrade 'n' stuff...
« Reply #5 on: November 22, 2012, 06:49:47 pm »
I really do appreciate the time you're spending helping me guys. The unfortunate thing about not knowing something is you don't know you don't know!

This is the system I purchased 2 years ago after taking advice at the time.


The very best TDS I got from this system when it was brand new was 016ppm prior to resin from 186 TDS tap water. My water pressure at the time was 65 psi and I didn't use a pump. I bought the pump, from the same supplier, a little while later when I knew I was moving home. I have changed the pre-filters every month and I did change the pre-filters before the upgrade. Since purchase I have replaced the membrane housing once and the membrane twice, the last time just under a year ago.

Once I moved I started using the pump as my water pressure was around 40 psi. I currently have no means to test the pressure of the water after the pump.


This is a better photo of the auto cut off that came with my system. There was no additional items with this and I can't see how I would add a float valve?


I think Alex is confirming my original membrane is contaminated and I'm ordering a replacement now. I'm just  a little concerned that I'm throwing good money after bad and that maybe it's time for me to consider replacing this system?

Duncan

dd

  • Posts: 2527
Re: RO Upgrade 'n' stuff...
« Reply #6 on: November 22, 2012, 09:55:46 pm »
I like that type of RO unit. Production rate is slow but product water is good in my experience, so I find it ideal for a single operator using a static system.

Would have thought the pre-filters should go 4 months before being replaced.

I have mine connected to a 1500l tank and usually run it for 2-3 days then turn it off for a few days until tank is near empty again.

Washing Windows

  • Posts: 95
Re: RO Upgrade 'n' stuff...
« Reply #7 on: November 24, 2012, 03:08:07 pm »
I've stripped back the RO to a single 100 gpd membrane, removed the resin and measure the output from both the old and the new membranes.

Lesson learned: always test before upgrading.

The old membrane, albeit less than a year old, is clearly a significant part of the problem with an output of 063 ppm. I’m not really sure what has caused this because I definitely change the pre filters every 6 to 8 weeks and I flush the system regularly. I’d really like to get to the bottom of this and would appreciate any thoughts?

To qualify, the RO system is 2½ years old and has 2 pre filters.

  • I usually buy my prefilters from cleaningspot.co.uk as I like their free delivery option if you spend £45 and the fact they use DPD, who send me a text with an hour delivery window on the morning of delivery.

The filters I buy are: a 10" Cartridge sediment filter 5 microns and a 10" Cartridge carbon block filter 5mic. Please can someone confirm I am buying the correct pre filters?

  • note: The 10" Cartridge sediment filter 5 microns I used to get from cleaningspot were very tightly wound and in a tight fitting cellophane wrapper. More recently they have been sending me less tightly wound 10" Cartridge sediment filter 5 microns in a paper wrapper, which I don’t think are as good?

With the new housing and membrane the TDS drops to between 011-012 ppm, which is much better and is around what I remember after testing when the system was new (or after fitting a new membrane). I've got another new 100 gpd membrane arriving on Monday, so with this fitted I can re-upgrade to 200 gpd and I should expect a similar reading prior to resin?

I’m a little concerned that my readings are almost double those that Alex and dd suggest I should be getting. I’m wondering if ‘like for like’ is being compared because I’ve noticed there are some RO systems with a third pre filter? I currently have inline a 550 rated flow restrictor, could this have much bearing?

I’ve tested my tap water pressure again to day and it’s 44 psi. My pump says it requires an input of a minimum of 35 psi, so that should be OK. The pump says it delivers a working pressure of 100 psi, so that should be OK too and although I don’t have any means to test it, it appears to be working fine.

From the picture included in my first post, have I fitted the upgrade correctly to minimise waste water?

Any thoughts, suggestions, criticisms and pictures of lewd women are very much appreciated.

Duncan

Nick_Thompson

  • Posts: 810
Re: RO Upgrade 'n' stuff...
« Reply #8 on: November 24, 2012, 03:54:26 pm »
Duncan

When my membranes are new they are producing about the same tds readings but after a week or so they start coming down until they reach 3 - 5 ppm.

Nick
Do quantum mechanics fix old transits?

And let us not forget, voyeurism is an occupational hazard that we simply must endure.

dd

  • Posts: 2527
Re: RO Upgrade 'n' stuff...
« Reply #9 on: November 24, 2012, 04:12:16 pm »
I have 3 100gpd membranes. When I first got the RO from cleaning spot I tested the membranes individually. 1 gave tds 004 the other 2 were around 024 after hours of flushing) . I complained to Ro-Man who supplied the RO to cleaning spot and they sent me 2 new membranes which both were fine.

When I replace membranes always flush for 2 hours or more but the tds still comes down a little with regular use.

I was told if membranes are stored too long they can break down.

After recently changing membranes my tds is around 006 where it used to be around 003 before, so I think there is a little variance in performance of membranes.

paul saunders

  • Posts: 1110
Re: RO Upgrade 'n' stuff...
« Reply #10 on: November 24, 2012, 04:27:17 pm »
Your pipework is right if you want to reduce your waste output, but, by doing this you will produce a higher overall TDS because the water going ito your second membrane is the waste from the first membrane and the TDS will be much higher than the water that is going ito the first membrane. Also the 550 restrictor is wrong, it should be a 200gpd restrictor. Also, I don't think that your pump is upto the job, I could be wrong about that but I think they are only good for upto150gpd.
I can remember when waking up stiff in the morning was a good thing.

Washing Windows

  • Posts: 95
Re: RO Upgrade 'n' stuff...
« Reply #11 on: November 24, 2012, 04:29:30 pm »
What size flow restrictors are you guys using?

Duncan

dd

  • Posts: 2527
Re: RO Upgrade 'n' stuff...
« Reply #12 on: November 24, 2012, 04:33:22 pm »
Your pipework is right if you want to reduce your waste output, but, by doing this you will produce a higher overall TDS because the water going ito your second membrane is the waste from the first membrane and the TDS will be much higher than the water that is going ito the first membrane. Also the 550 restrictor is wrong, it should be a 200gpd restrictor. Also, I don't think that your pump is upto the job, I could be wrong about that but I think they are only good for upto150gpd.
I have 3 membranes so water is recycled twice but still get 006.

No idea what size flow restrictor, just what came with the system.

Washing Windows

  • Posts: 95
Re: RO Upgrade 'n' stuff...
« Reply #13 on: November 24, 2012, 06:36:50 pm »
When my membranes are new they are producing about the same tds readings but after a week or so they start coming down until they reach 3 - 5 ppm.
When I replace membranes always flush for 2 hours or more but the tds still comes down a little with regular use.

I was told if membranes are stored too long they can break down.

After recently changing membranes my tds is around 006 where it used to be around 003 before, so I think there is a little variance in performance of membranes.

Hey, I think I’m seeing a pattern here!

They say you learn something new every day... apparently today’s lesson was flush membranes thoroughly for a couple of hours once installed. You would think it would say something on the membrane? :(

Your pipework is right if you want to reduce your waste output, but, by doing this you will produce a higher overall TDS because the water going ito your second membrane is the waste from the first membrane and the TDS will be much higher than the water that is going ito the first membrane.

Makes sense but I would like to reduce my waste ideally as I’m on a water meter and my supplier said to do it this way for this reason (although I wasn’t sure if I’d done it correctly)

If I picked up the feed directly after the two pre filters rather than after the first membrane, the second membrane would be running in parallel rather than series (as I’ve done it) and the TDS should be lower?

Also the 550 restrictor is wrong, it should be a 200gpd restrictor.

Here’s what my supplier said when I asked: >:(

Quote from: supplier
There isnt a right or wrong restrictor within certain parameters.
 
If the restrictor is far too small it increases pressure in the system forcing more water through the membranes so the pure to waste is better but the TDS is slightly higher. Conversley if the restrictor is too large the pure to waste is worse but TDS output can be better. Altering the restrictor one size one way or the other makes minimal difference.
 
On a 200gpd system the makers fit a 800 but I found swapping it for a 400 made a vast difference to pure to waste ratio with little increase in TDS so I suppose it is a matter of try it and see.

Also, I don't think that your pump is upto the job, I could be wrong about that but I think they are only good for upto150gpd.

Really? How can I check?  ???

Duncan

paul saunders

  • Posts: 1110
Re: RO Upgrade 'n' stuff...
« Reply #14 on: November 24, 2012, 07:01:15 pm »
You need a pressure gauge, test the pressure with one membrane  plumbed in, then test the pressure with both membranes plumbed in. If there is no noticeable pressure drop then it is ok.

Have you measured your pure to waste ratio? you should be getting about 1L of pure to 3 or 4L of waste.

It's ok your supplier saying what he has but if you have the wrong restrictor you  could be putting far too much waste water down the drain, as you are on a meter, that waste water could be costing more than it would cost for the resin.
I can remember when waking up stiff in the morning was a good thing.

Gary f

  • Posts: 121
Re: RO Upgrade 'n' stuff...
« Reply #15 on: November 24, 2012, 07:30:59 pm »
Hi I have siiliar howether dont use pump and use http://www.gardinerpolesystems.co.uk/acatalog/1-4-inch-push-fit-in-line-valve.html  to control waste toproduct ratio works fine and brings down from 230 pp -010ppm.

I change my filters once after 3 months from vyair and everything good.

Hope that helps

Link to set up auto shut off valve

http://www.youtube.com/watch?v=ssa6njb5nV4&feature=related

s.w.c

  • Posts: 1174
Re: RO Upgrade 'n' stuff...
« Reply #16 on: November 25, 2012, 02:08:09 pm »
i used a something like your for five years, i finally got it upgraded to a better system, so much better, alex sorted me a adjustable flush valve, then i added a extra twist so i could isolate di when back flushing with a couple of taps and a t-bit so simple but helps the life of the di hugely, when you get chance get one you wont regret it.








Washing Windows

  • Posts: 95
Re: RO Upgrade 'n' stuff...
« Reply #17 on: November 25, 2012, 04:05:56 pm »
You need a pressure gauge, test the pressure with one membrane  plumbed in, then test the pressure with both membranes plumbed in. If there is no noticeable pressure drop then it is ok.

Have you measured your pure to waste ratio? you should be getting about 1L of pure to 3 or 4L of waste.

It's ok your supplier saying what he has but if you have the wrong restrictor you  could be putting far too much waste water down the drain, as you are on a meter, that waste water could be costing more than it would cost for the resin.

Thanks for that Paul. I’ll get a pressure gauge ordered this week, is there one you recommend?

The replacement membrane arrives tomorrow and once I’ve upgraded the system again to 200 gpd I will measure the pure to waste ratio as you recommend.

I’m struggling a bit with the flow restrictor! I’ve spend a good few hours browsing the web to try to find information and a supplier of the correct size. Any help with this would be very much appreciated?

My original supplier said that manufacturers ship the 200 gpd systems with an 800 rated flow restrictor. The closest I’ve been able to find to this is an 850 that Cleaningspot have but has been showing out of stop for weeks. I did email them a week or so ago but no reply.

Link to set up auto shut off valve

http://www.youtube.com/watch?v=ssa6njb5nV4&feature=related

Cheers Gary. A really useful link and I spent a good hour this morning watching all their RO related videos, which has really helped me understand my system a lot better.

i used a something like your for five years, i finally got it upgraded to a better system, so much better, alex sorted me a adjustable flush valve, then i added a extra twist so i could isolate di when back flushing with a couple of taps and a t-bit so simple but helps the life of the di hugely, when you get chance get one you wont regret it.

Nice looking system mate!

I don’t have huge amount of spare cash available and this system has been working well enough for me for the last couple of years. I’ve learnt a hell of a lot from this thread and I should be able to upgrade what I have without too many issues (you’d think ;)).

I’ll keep updating as I go for anyone interested but at the moment it’s working in progress and I’m grateful for any advice.

Duncan

s.w.c

  • Posts: 1174
Re: RO Upgrade 'n' stuff...
« Reply #18 on: November 25, 2012, 04:37:58 pm »
its always a working progress  ;D its taken me 8 years and still a working progress

Gary f

  • Posts: 121
Re: RO Upgrade 'n' stuff...
« Reply #19 on: November 25, 2012, 05:24:30 pm »
Float valve i believe can be fitted inn your static and when level reached float lifts shutting all flow up. Hole drilled waher or ptfe tape to stop leaks etc. Lifts float and water stops.

I looked at your photo and blue valve on system looks similiarto mine on way is water production and one is used to flush membranes.