Ro/di

[Jetdrvr]

WHat RO/DI systems are you all using? Is there one that is the most popular among everyone? I have a Kent Marine one that is a real piece of crap. It's a 60gpd unit and I am lucky if I get 8 and thats with a booster pump. HELP!!!!!!!

[lecher]

I have the kent marine hi-s 60 gpd and I get pretty darn close to that out of mine with a 0 tds reading. Has alot to do with water pressure, temp, age of filters. Do you have/use a back flush. It helps keep the membrane cleaner longer. Might want to check the restrictor.

[AZDesertRat]

Two factors that affect all membranes no matter what brand are pressure and temperature. 8 GPD sounds pretty poor. What is the water temp, what booster pump do you have and how is it plumbed. How old is the membrane and the pre and carbon filters and how often do you change them out and disinfect the housings? What is your waste ratio/flow restrictor set at? I am neither here nor there on flush valves until someone proves to me they do anything at all besides lighten your wallet.

[Jetdrvr]

It comes off the cold water line so it's pretty cold but I'm not sure of the temp. I forget what pump I have, I got it from Fosters and Smith. I change the carbon and sediment pre filter when they look dirty and my output drops but when they are brand new I'm probably at maybe 12gpd. I'm not sure how to set the waste ratio/flow restrictor and I do have a flush kit on it.

[AZDesertRat]

Do you have a pressure gauge so you can tell what pressure you are actually delivering to the membrane? Measure your waste flow and product flow with a measuring cup. The waste should be about 4 times the product flow so say you time each one for 5 or 10 minutes and see what you come up with. Changing filters when they look dirty is not a very scientific method of doing it, you need to change them every 6 months at a minimum with quality replacements and disinfect the housings. How old is the membrane? Do you have a TDS meter and can you check the tap water TDS and RO TDS to see how well its working? Your membrane could be plugged with that low of a production rate.

[Roland Jacques]

i would guess something not hooked up right. try bypassing your auto shut off valve (if you have one that where i would start) post a photo if you can.

[Jetdrvr]

The waste is a constant flow and the output is about a drop every 2 seconds. I change the pre filters every 2-3 months because they look horrible that fast. I changed the membrane last year and got about the same result when it was new as I am getting now. I don't have a pressure gauge or a TDS meter, should I get those or spend the money on a new system that incorporate those in it. I mean, my water can't be that bad and my pressure that low to have all of these problems, right?

[Roland Jacques]

i have seen cloged prefilters that stoped production all together.

[Roland Jacques]

im sorry I thought you had checked your pressure already. that should be #1 and it can definitely cause low production.

you need at least 50-60 psi to operate most any RO.

[AZDesertRat]

Cold water affects output so if your water temperature changes significantly from season to season its wise to have an adjustable flow restrictor. It sounds to me like your waste flow is much more than 4 times the product or good flow. If that is the case then you need to slow the waste stream down in order to provide sufficient pressure to push water through the membrane. With no restriction which is what the flow restrictor does it just bypasses the membrane and flows to waste.
In order to troubleshoot the system you really need to know pressures, temperatures, TDS readings from tap, RO only and RO/DI if you have DI and the waste ratio. Without all that its a shot in the dark and who is to say a brand new system would not do just the same. The Kent is an above average system so if its not performing well I tend to think its not the system but other factors. I would buy an inline pressure gauge and a handheld TDS meter first, they can still be used even if you decide to buy a new system later but without them now its hard to pin anything down. You might also buy a 1/4" john guest ball valve and stick it on the waste line to see if slowing the waste flow down to the 4:1 ratio helps, I'll bet it does.

[Jetdrvr]

thanks for all the advice. I have a 1/4" Ball valve that I'll stick on the waste line tonight. I will order a pressure gauge and TDS meter today. I originally bought the 35gpd system and then later bought the 60gpd membrane and flow restrictor. I put the flow restrictor where the output line leaves the membrane cartridge, was this correct? Could I have done someting wrong when I changed these things? Also would it help if I moved my pressure pump from before the prefilter cartridges to right before the membrane? I can easily do this also.

Thanks again

[AZDesertRat]

The flow restrictor goes on the waste line to the sink drain or where ever you waste to.

[Jetdrvr]

Does it go at the end of the line where the water goes out into the sink or where the waste water enters the line right at the membrane.

[AZDesertRat]

Generally they are right close to the housings but thats probably to make the unit compact more so than anything else. The vendors have no control on how your final plumbing looks so they provide everything in a nice tight compact unit.
I don't think it really matters where its located as long as its on the waste line.
Lots of the vendors have generic drawings on their sites that show the way the lines run and what goes where. Its very easy to replumb an autoshutoff valve or the membrane housing incorrectly when doing maintenance, I've done it wrong myself on more than one occasion.

[Jetdrvr]

I will try to find a drawing and make sure I have it right. I just ordered a pressure gauge and TDS meter for Premium Aquatics. I also ordred new prefilters. What micron size do you use? I ordred 1micron sediment and 5 micron carbon block. I am wondering if I have the .1 and .5 on there now and that may be causing me trouble. I will check my restricor tonight and add the ball valve and see if that helps me out at all. Thanks for all your advice.

[AZDesertRat]

I use a 0.5 micron prefilter and 0.5 micron Chlorine Guzzler carbon block and have a 3 to 4 lb drop across the filters, 68 in and 65 out normally. As long as you have somewhere in the 50 to 60 psi range pressure across the filter array should not be a problem unless you have high suspended solids like iron or sediments which could cause filters to plug prematurely.
When it comes to RO/DI I try to deal with vendors that deal exclusively in water treatment like:
www.spectrapure.com
www.buckeyefieldsupply.com
www.thefilterguys.biz
or
www.purelyh2o.com
All are RC sponsors and very aware or reef systems and their needs. All they do is water treatment so they can answer all your questions and sell you only what will work for you and not some off the shelf packaged one size fits all solution.

[mg426]

I would take AZs advice he has helped me out a couple of times and knows RO/DI systems.

[Jetdrvr]

What RO/DI system do you have AZ? I am going to try everything you said tonight when I get home from work but if I cant get this one working I am going to but a new system from someone that will support what they sell. I am not getting a response from the Kent Marine tech support.

thanks again

[AZDesertRat]

I have this one here:
http://www.spectrapure.com/St_MaxCap-RO-DI.htm

[taylor t]

My temp out of the tap was 55 degrees. I raised it by adding a 50 foot coil of 1/4 inch tubing on the feed line submerged in warm water. I left it in a 5 gallon bucket with a heater and a power head in it to raise it to 80 degrees. It helped to raise the waste pressure to about 75 psi. I had the same kent a while back. made a big difference for me. Good luck.

[Jetdrvr]

I found out tonight that the pressure on my booster pump was adjustable, I found a small allen screw on the front of the pump and I turned it counter clockwise a bunch. It boosted my wastewater and seems to have increase my output but it is still measured in drops. When the pressure gauge gets here tomorow I will know for sure. I think I will also try the heater in the bucket trick. Well see what happens.
AZ, I am thinking of just getting the spectra pure that you have, do you think I would see a big difference with it or can I get the Kent to give me what I need?

Thanks

[AZDesertRat]

Call or e-mail bruce@spectrapure and ask his advice. I am very happy with my MaxCap system but my water temp is higher and pressure is good. It should perform well for you too but I'm not the person to talk to since I'm just an end user myself. I will say if you are thinking about a new unit they don't come any better than this one though in my opinion.

[Jetdrvr]

Thank alot AZ. I will check my system tonight with my pressure gauge and TDS when it arrives and see what I can figure out. Then if I am still thinking of switching I will get in touch with Bruce. Thanks again

Joe

[Jetdrvr]

Ok, I got my stuff today. I am running at 60psi after the prefilters with the booster pump, my TDS out of the tap is in the 196, it getting down to 34 after the RO/DI but even with new pre filters I am still only getting a drip every other second or so. Any other ideas? My temp is in the 50's, I know I should raise it but how? Will that coil in the bucket work and still give me the pressure I need? What about my TDS, it still seems awfully high to me.

Thanks again

[mburnickas]

I have a Kent and it is fine. Been almost 3 year. It depends on Tap water quality. Mine is 36 PM of TDS and works jut fine. RO is going on 3 years and up to 5 ppm TDS... After DI zero.