DIY RO unit

[DaveB]

Duncan
I will shortly be in the process of assembling a 2 x150GPD unit. ( Hope I have got all the necessary parts). I have notice that in most of the assembled units from ROMAn the membrane housings are all horizontal except this model
http://www.ro-man.com/shop/popup_image.php/ ... b103f3b588" onclick="window.open(this.href);return false;.
My only concern is that all the air is not expelled when first filling the unit. Your views would be appreciated.Any tips /or advice when installing membranes into the housing or is it just straight forward. I am also assuming that the restrictors can go eitherway.
Best Regards DaveB

[Gazza]

Hi Dave,

Just open the box get all the gear out and go for it by the end of next week you will be saying,well this RO stuff is easy

It all fits together very straightforward and i am sure you will have it up and running in no time...well hopefully now as it PM

[DaveB]

Cheers Garry
Its now running but not giving as much water as I would have like 117 gallons per day. TDS 2ppm. Waste water looks to be more but as yet not measured it. One thing which was confusing. The membrane fittings were not attaced to the housings and two of them have check valves in them. Accordeing to ROMan both product and waste water should both have check valves on outlet of membranes housings(not sure why). Anyway they only sent 2 so I fitted these to the product outlet, as the waste will have the restrictors which I asumed as they are one way only ,so these also have check valves. The restrictors are for 150 GPD 3-1 and the mains pressure is still above 60psi whilst every thing is running. Perhaps if I swap the check valves over to waste outlets this would help.Any other ideas to get a better rate.

[Gazza]

Hi Dave,

What no pictures lol

117gpd with no pump not bad if i run mine without the pump its pants

Not sure about the check valves as i have none on mine as its all done as per the drawing and my waste is defiantly lots less than my product water.i know this as i have got it going again today after busting the pre filter

[DaveB]

Hi Garry
Thanks for the imput Here is a photo of all the pieces.

IMG_0758.JPG (73.64 KiB) Viewed 24518 times

The small white 90 bends on the right of the housings have check valves(non return) fitted.
According to ROman these should be fitted to both product and waste. ( So how would I backflush if non return valves are fitted and why only supply two)
I will ask ROMan on Monday when they open again.
Here is another photo with everything assembled and working.

IMG_0760.JPG (84.36 KiB) Viewed 24518 times

Good news is I have just done another check and the product water is 147 GPD and waste water is 211 GPD. so some improvement on yesterday. Still wondering if those check valves are creating any back pressure in the product water and reducing the flow.Can you confirm that the valves fitted to your membrane housings do not have check valves in them.If so I will remove them.
At present I have approximately 50% RO and 50 % purified water going in which is about 5% pond volume per day.Which is fine but will probably take a long time to reduce my G.H.
I apologize if the photos are not a very good size perhaps there is aprogram to change files to the correct size you could recommend
BestREgards DaveB

[Dave Collins]

Here's a brilliant resize program

http://www.rw-designer.com/picture-resize" onclick="window.open(this.href);return false;

nice RO unit, I'm waiting to see the results before going forward

rgds

Dave

[DaveB]

Dave
Thanks for the program link. I will keep this forum posted with developments. Best Regards Dave

[brians]

Dave
it is worth bearing in mind
that the membranes are rated at a water temp of 25 degrees
on the RO man site there is a list of corelation figures for different temps
for example if your source water was at 9 degrees C there is a corelation factor of 2 which means
that the flow is halved
This is always worth bearing in mind

Brians

[Gazza]

All this talk of RO and off i go messing around and bugger up my membranes

Don't ya just love this stuff

[DaveB]

Dave
it is worth bearing in mind
that the membranes are rated at a water temp of 25 degrees
on the RO man site there is a list of corelation figures for different temps
for example if your source water was at 9 degrees C there is a corelation factor of 2 which means
that the flow is halved
This is always worth bearing in mind

Brians

Good to hear from you once again. Hope you are OK. Thanks for that.Nice one. I used the system preformance tool and typed in the various pressures and temps and it worked out exactly right .Looks like I won't be making as much water during the winter. Here is the link for anyone else who wishes to try it.
http://www.ro-man.com/ro-man_support.html" onclick="window.open(this.href);return false;
Best REgards DaveB

[MikeH]

Watching with interest Dave, I believe I`m on the same water supply as I live in Newton Aycliffe. I have just received my tds meter through the post this morning so will check its calibration then get some readings. took some tonight and they were tap 85ppm pond 97ppm and thats without a contant flow of fresh water flowing through an overflow system, although I do clean the nexus most days. If they can be varified then I will be fairly pleased as so far I have only been aiming to maintain healthy parameters for ph, ammonia, nitrite and nitrate as well as keeping the filters clean. I beleive I have low kh but I`m not sure about gh. What test kits would you recommend for measuring kh and gh?

[DaveB]

Watching with interest Dave, I believe I`m on the same water supply as I live in Newton Aycliffe. I have just received my tds meter through the post this morning so will check its calibration then get some readings. took some tonight and they were tap 85ppm pond 97ppm and thats without a contant flow of fresh water flowing through an overflow system, although I do clean the nexus most days. If they can be varified then I will be fairly pleased as so far I have only been aiming to maintain healthy parameters for ph, ammonia, nitrite and nitrate as well as keeping the filters clean. I beleive I have low kh but I`m not sure about gh. What test kits would you recommend for measuring kh and gh?

Hi Mike sorry for the delay in replying. That looks to be very similar to where I was running my pond before the RO unit was fitted, perhaps a shade lower. But it might be just the difference in temp or that my meter has not been calibrated in new cal solution only old for sometime.Regarding the K.H & G.H test kits. I believe that API do a combined one which is liquid drops which is waht I prefer. If you double up the amount of water to be tested to 10ml then twice as many drops are required for the same reading which gives greater accuracy.
best Regards Dave

[MikeH]

Hi Dave, my next project is to include heating and then an topup/constant water feed & overflow system to try and get the TDS as low as possible and to reduce any excess GH that may be present. I have a kusuri GH/KH tablet test kit however I`m not sure how reliable they are. Well I`m signing off, gonna clean the filters before work...

[mio]

Hi Dave, my next project is to include heating and then an topup/constant water feed & overflow system to try and get the TDS as low as possible and to reduce any excess GH that may be present. I have a kusuri GH/KH tablet test kit however I`m not sure how reliable they are. Well I`m signing off, gonna clean the filters before work...

Hi Mike ..

Kusuri or any Tablet/Powder Test Kit should be even more Accurate than their Liquid reagent Counterparts although the others are acceptable when applying the doubling of test Water Technique ..

Dave Well Done Your the First to Post on the DIY R/O System all Thank`s to Dunc of course for saving the members ££££££S

[DaveB]

Hi Dave, my next project is to include heating and then an topup/constant water feed & overflow system to try and get the TDS as low as possible and to reduce any excess GH that may be present. I have a kusuri GH/KH tablet test kit however I`m not sure how reliable they are. Well I`m signing off, gonna clean the filters before work...

Hi Mike
Please Keep us posted of your future developments.
After two weeks changing 5% pond volume per day, 50% RO 50% purified. I have reduced the G.H. of pond water from 70 to 50ppm. and TDS to 75ppm. I have had to add small amounts of bicarb to maintain a k>h of 30ppm. This morning the p.H as got down to 7.0. The p.H is fluctuating a little more than I would like 0.4. on suuny days But koi do not seem to mind. I realize this is probably due to photosythisis of blanketweed/algea, but as this is hardly detectable ( First time ever I have not had to treat for blanketweed in april) I am hoping that once I get my G.H below the k>H without increasing the TDS too much that the p.H will stablize. ( still not sure why this is so ???) I am just about to fit a metals removal cartridge to my exsisting 2 pod purifiier, after getting a recent water quality report in the the hope of improving the water supply even more. I understand that this too may have an effect of lowering the p.H( don't know why, perhaps some metals actually increase p.H.???) but will be monitoring things closely
Best Regards Dave