Rodi sytem remodel

[DonW]

I think I finally have all the piece to remodel my rodi. I have all the filters, wires and hoses strung all over my laundry in a huge web of mess. I'm going to get everything mounted up on a single board all neat and tidy. I'm getting rid of the tds controllers and am going to just flush every cycle instead of being tds based. After adding the second membrane water waste is next to nothing so I'm not going to worry about saving water. Here is a diagram of the major parts.

Don

 

[Krish]

McGuyver...You sure are always up to something! Almost as bad as me!!!(LOL) Looks like a very neat setup which I'm sure you will get running smoothly so make sure to post your progress

 

[DonW]

McGuyver...You sure are always up to something! Almost as bad as me!!!(LOL) Looks like a very neat setup which I'm sure you will get running smoothly so make sure to post your progress

It works great as is, but sure is a mess. Ive added on alot of stuff one at a time and never organized any of it.

Don

 

[Krish]

I need to make a trip to Washington when you get all your projects finished and see what a fully automated DIY reef aquarium looks like

 

[RandyStacyE]

Since you are using 2 membranes, how are they plumbed? Do you just run them side by side with their own separate feed lines, separate waste water lines, 2 separate flow restrictors and direct both of their outputs to the next stage?

I didn't see a booster pump in the pic, but with such a large system I assume you're using one right?

From the diagram I assume you run your RO/DI water through a final carbon filter. I always thought that the DI was the final stage to remove any last traces. Do you find that it works best that way?

 

[DonW]

Since you are using 2 membranes, how are they plumbed? Do you just run them side by side with their own separate feed lines, separate waste water lines, 2 separate flow restrictors and direct both of their outputs to the next stage?

I didn't see a booster pump in the pic, but with such a large system I assume you're using one right?

From the diagram I assume you run your RO/DI water through a final carbon filter. I always thought that the DI was the final stage to remove any last traces. Do you find that it works best that way?

Membranes get plumbed one after the other thats why you get the efficiency. Just one inlet and one outlet but they have to be matched 75gpd/75gpd. No booster pump needed my pressure at the first membrane is 85, but you need at least 60. The final carbon stage is to remove any breakdown of the di's.

Don

 

[RandyStacyE]

Membranes get plumbed one after the other thats why you get the efficiency. Just one inlet and one outlet but they have to be matched 75gpd/75gpd. No booster pump needed my pressure at the first membrane is 85, but you need at least 60. The final carbon stage is to remove any breakdown of the di's.

Don

Ok, the membranes are plumbed inline, but you do have 2 separate wast to drain lines right (one leaving each membrane)?

 

[DonW]

Ok, the membranes are plumbed inline, but you do have 2 separate wast to drain lines right (one leaving each membrane)?

The second membrane is fed by the waste line of the first membrane.

Don

 

[RandyStacyE]

Got it now! Thanx

 

[DonW]

I'm going to be putting most of this mess together tonight except the second membrane which I broke. Trained apes shouldnt be allowed to do this stuff. Has anyone had a algae problem in the tube with using clearish rodi tube from Home depot. It may get some sunlight through the window.

Don

 

[RandyStacyE]

I never had algae in the RO or RO/DI output lines. I used clear hose for some of the other jumper lines and they are maroon red now because of the rust in my well water.

 

[DonW]

Here is the basic rodi system. I wont add the solenoids and two other pressure gauges until I get the replacement membrane for the one I broke.

 

[DonW]

Not much getting done this week-end. Here is the conductivity controller, solenoids and conductivity probe.

 

[DonW]

Well bummer the conductivity control is a absolute flop. The dc solenoids must be putting a small amount of voltage in the water. The control sees this voltage and turns on the dump valve full time. I tried grounding both the the solenoids and the water but no such luck. I want the system completely self contained and not tied to the automation contoler via cat 5 so back to the drawing board.
I am working on a pressure type add-on system so that folks can add this feature to their existing rodi systems but am a few weeks out. I may just wait and use one myself. Spectrapure just came out with a complete rodi system that does this but $400 is a bit tough to swallow. I'm hoping to make them much cheaper.

Don

 

[Scooterman]

Couldn't you use isolating relays maybe? Guess that would get a little expensive.

 

[DonW]

Couldn't you use isolating relays maybe? Guess that would get a little expensive.

Basicly it would need 0 contact solenoid valves. All the affordable ones have a tiny ring that is exposed and are cooled by the what ever is flowing through them. It can be done with $150 valves but thats kind of crazy.
I already have the control timer board in production and will be to me in a few days.
What its designed for, is a system that uses the rodi to top off a sump by either a solenoid or float valve. Each time the float valve opens it sees the pressure drop, then turns on the dump for a adjustable amount of time after the dump is complete it turns on the top off until the float valve closes. Once pressure is high enough to shut off the asv the board shuts down until next time around.
The board can be used without a pressure switch and just put on a timer. This would give you a second and third layer of redundance along with the tds creep flush.

Don

 

[DonW]

Alright here is the fix for the previous hang up. Very simple and can be used with any float valve or solenoid valve type ato system. The ato is just a solenoid that opens the rodi line to the sump, this new gizmois just a add-on.

First is the pressure switch. If the ato turns on the pressure will drop below 20psi. This sends power to the timer board. The board turns on the dump solenoid for a time from 0-60 seconds or 0-60 minutes depending on the jumper settings. After the dump cycle the board closes the dump and opens the clean water solenoid. When the tank is full the ato shuts off and the pressure rises. When it hits 20psi it shuts down the clean water solenoid. Finally when the pressure reaches 90% of line pressure the rodi asv will shut down the input and waste.

 

[RandyStacyE]

Where did you aquire the timer board and the pressure switch? I don't recall if you already posted that.

 

[DonW]

Where did you aquire the timer board and the pressure switch? I don't recall if you already posted that.

I have the boards made by a electronics design company in NC. The switch just comes from Omega.

Don

 

[DonW]

Well this project is done and what I would concider a success. I collected all the dumped water yesterday almost of a gallon. The ato cycled 3 times at just under a gallon each. The conductivity of the dumped water was 62 us/cm and the top-off water 0 us/cm.
I dumped the 62 us/cm into 2.75 gallons of 0 us/cm 0 TDS water then tested the TDS with a regular freshly calibrated TDS meter. The meter calculated the TDS at 8.

So basicly with a tap tds of averaging 30ppm without the bypass the 10stage rodi would be putting 8tds water in the tank, with it you get 0. I would concider 8 a pretty high number. I'm almost positive if the tap tds was alot higher the 8 would be much higher.

Don