Is my RODI Unit Setup Correctly? *See Pics*

[CoralReefer1019]

Just replaced my DI Resin, Carbon and Sediment Filter and I was wondering is my RODI unit setup correctly? My TDS out is “0” and it’s hooked up in-line after a whole house water softener. If you look at the pics coming out of the RO Membrane there is a black and white line going into a plastic housing of some sort then into a gray adjustable valve. From there it goes to the DI chamber and wastewater line. Just want to make sure everything is setup correctly.

 

[miPapareef]

I don’t think it’s plumbed correctly. The white part with the white and black tubes is called an auto shutoff valve. I haven’t seen a system where the waste line, black tube, is plumbed through the auto shut off. My system that came from BRS has the line between carbon block to DI going through the auto shutoff.

Also, I don’t see a manual flush valve in any of your pictures. It should be on the waste line and allows you to flush the RO membrane and extend its life. Like this https://www.bulkreefsupply.com/membrane-flush-valve.html

Here’s how it should be plumbed.

• Water in goes into the sediment filter.
• It will flow through two the sediment filter and the two carbon block filters.
• When it comes out of the carbon blocks it should go through one side of the auto shutoff and then to the RO membrane. (This is the tube that has the pressure gauge in your setup)
• The RO out line, white tube, goes through the other side of the auto shutoff and then to the DI filter.
• The waste line out, black tube is the waiste water and should go directly to the drain.
• The DI out line is the one with the TDS out and is your RODI water for the aquarium.

Your plumbing has the waste line going through the auto shutoff, which I have seen before.
Also you have a the waste line tied into the RO out after that 3 way valve. Makes no sense to me. Maybe that is some attempt at a bypass flush for the RO membrane.
You should probable get a flush kit to do this properly.

Pic for clarity

 

[DLHDesign]

I actually think it's all plumbed correctly. Not the same as a BRS kit, but it looks like your flow path is correct.

1. Water enters the sediment filter (pic 1, lower red line) and flows through the filter and both carbon blocks (not pictured).
   
2. Exiting the 2nd carbon block, it flows through the pressure gauge (pic 2, middle white) and into the RO membrane.
   
3. The clean water runs out the white line, through the trigger side of the shut-off valve, into the initial TDS meter, and then into a 3-way valve (pic3, etc.)
   
4. The waste water runs out the black line, through the controlled side of the shut-off valve, into a y-splitter (y-union in this configuration) and (presumably) out to the waste plumbing (pic 3, etc.).
5. Out of the DI chamber, you run through the exit TDS meter and into your storage tank (pic 1) - where presumably it's hooked into a float switch or the like?
   
6. From the 3-way valve, the position pictured diverts the clean RO water into the DI chamber, etc.
7. If the valve is flipped the other way (pointing down), the clean RO water will be diverted into the y-splitter and out into the waste line. As this is basically diverting all the water into the waste, this acts as a "flush valve" for your system. You'll want to run it in this "flush configuration" for a few seconds both before and after each use. You could do away with this 3-way valve entirely if you purchased an appropriate flush valve like those @miPapareef linked to above - which would have the added advantage of giving you a flow restrictor - which helps to ensure your RO membranes are being optimally utilized.
8. When the storage container is full and triggers the float switch, the pressure in the clean RO line will grow. This pressure will cause (because of the shut-off design) the waste line to also be closed. With both the clean and waste lines shut, this effectively stops the water flowing into your system - giving you an "auto-shutoff". Because it's the entire clean-water line that is doing the triggering, it doesn't really matter all that much where the shut-off is located (pre- or post- RO chamber).
   Some other configurations I've seen will put the shutoff control side on the input line of the system. With that setup, when the tank fills up, it shuts down the entire input water source. This keeps the RO/DI system from being in a pressurized state - not really a big deal since it's unlikely that such a state would cause any issues.

Note that if you don't have a float switch in your storage container, the auto-shutoff valve isn't doing anything for you. It only comes into play when the clean water line builds in pressure. No harm in it being there in that case; just not doing anything beneficial.

 

[CoralReefer1019]

I actually think it's all plumbed correctly. Not the same as a BRS kit, but it looks like your flow path is correct.

1. Water enters the sediment filter (pic 1, lower red line) and flows through the filter and both carbon blocks (not pictured).
   
2. Exiting the 2nd carbon block, it flows through the pressure gauge (pic 2, middle white) and into the RO membrane.
   
3. The clean water runs out the white line, through the trigger side of the shut-off valve, into the initial TDS meter, and then into a 3-way valve (pic3, etc.)
   
4. The waste water runs out the black line, through the controlled side of the shut-off valve, into a y-splitter (y-union in this configuration) and (presumably) out to the waste plumbing (pic 3, etc.).
5. Out of the DI chamber, you run through the exit TDS meter and into your storage tank (pic 1) - where presumably it's hooked into a float switch or the like?
   
6. From the 3-way valve, the position pictured diverts the clean RO water into the DI chamber, etc.
7. If the valve is flipped the other way (pointing down), the clean RO water will be diverted into the y-splitter and out into the waste line. As this is basically diverting all the water into the waste, this acts as a "flush valve" for your system. You'll want to run it in this "flush configuration" for a few seconds both before and after each use. You could do away with this 3-way valve entirely if you purchased an appropriate flush valve like those @miPapareef linked to above - which would have the added advantage of giving you a flow restrictor - which helps to ensure your RO membranes are being optimally utilized.
8. When the storage container is full and triggers the float switch, the pressure in the clean RO line will grow. This pressure will cause (because of the shut-off design) the waste line to also be closed. With both the clean and waste lines shut, this effectively stops the water flowing into your system - giving you an "auto-shutoff". Because it's the entire clean-water line that is doing the triggering, it doesn't really matter all that much where the shut-off is located (pre- or post- RO chamber).
   Some other configurations I've seen will put the shutoff control side on the input line of the system. With that setup, when the tank fills up, it shuts down the entire input water source. This keeps the RO/DI system from being in a pressurized state - not really a big deal since it's unlikely that such a state would cause any issues.

Note that if you don't have a float switch in your storage container, the auto-shutoff valve isn't doing anything for you. It only comes into play when the clean water line builds in pressure. No harm in it being there in that case; just not doing anything beneficial.

I make my RODI water manully as needed in a 20 gallon brute in my garage. I don’t need the float valve as the container gets full i just shut off.

What I don’t under stand are the two lines coming out of the RO Membrane. It goes to a gray valve one end goes into DI resin and the other is waste water. Why does some go to waste water and the other does trough the DI resin?

 

[ChrisOFL]

I make my RODI water manully as needed in a 20 gallon brute in my garage. I don’t need the float valve as the container gets full i just shut off.

What I don’t under stand are the two lines coming out of the RO Membrane. It goes to a gray valve one end goes into DI resin and the other is waste water. Why does some go to waste water and the other does trough the DI resin?

It looks like you have a flush valve setup to me. Basically you would flip that grey valve so the "clean" water coming out of the RO membrane is sent down the drain when you first turn the unit on so high TDS water that has leached into the membrane housing can be flushed out before it reaches the DI cartridge. This will extend the life of the DI resin saving you tons of money.

 

[CoralReefer1019]

It looks like you have a flush valve setup to me. Basically you would flip that grey valve so the "clean" water coming out of the RO membrane is sent down the drain when you first turn the unit on so high TDS water that has leached into the membrane housing can be flushed out before it reaches the DI cartridge. This will extend the life of the DI resin saving you tons of money.

they have 2 outputs on the RO Membrane is because one is “good” water and the other is “bad” water ? Since I have been using this unit I never messed around with that flush valve, the valve does turn but I’m not sure what it does. I was just checking the TDS on my output as “0” I do want to prolong my RO Membrane and DI Resin

 

[ChrisOFL]

they have 2 outputs on the RO Membrane is because one is “good” water and the other is “bad” water ? Since I have been using this unit I never messed around with that flush valve, the valve does turn but I’m not sure what it does. I was just checking the TDS on my output as “0” I do want to prolong my RO Membrane and DI Resin

Yes on your unit it looks like black is waste and white is good water. When your RO/DI had been off for more than a few hours, high TDS water accumulates in the RO housing and when you turn it on it will send that high TDS water to the DI resin, depleting it faster. If you turn that grey valve it should cause the good water coming out the membrane to go down the drain with the waste water instead of going to the DI resin. You will want leave the valve turned until you see the TDS probe on the good water out the membrane fall to normal levels (this is 3TDS out the membrane for me).

 

[DLHDesign]

they have 2 outputs on the RO Membrane is because one is “good” water and the other is “bad” water ?

Yes; exactly. RO membranes don't work like standard filters that trap particles and just hold them until changed. The membrane traps the particles, but then uses a portion of the water flowing through to flush them out. This is where the quality of the membrane comes into play - the better membranes will be more efficient at this process (removing more material and/or using less water). This is also why you want to have a specific pressure going into your membrane - they process works best at a specific water pressure. You can get a lower quality membrane and/or use pressure that is slightly low or high and it'll still help, but more undesired particles will pass out of the membrane when that's the case. These particles pass into the DI resin, which is depleted faster as a result (read: more cost). The cost of DI resin is generally why it's a good idea to get a quality membrane and ensure that your pressure is correct - even to the point of buying a restrictor and/or buying a booster pump, if needed.
(Note that most membranes available on the market are all made by DOW, so it's really more about buying the right one for your water pressure and flow rate.)

Since I have been using this unit I never messed around with that flush valve, the valve does turn but I’m not sure what it does. I was just checking the TDS on my output as “0” I do want to prolong my RO Membrane and DI Resin

As @Cronicreefer stated above; you'll want to use the valve to force-flush the system at the start (and end, ideally) of a run. Basically; after you finish filling your container, turn the valve the other way (to "flush"), wait 30 seconds, then shut off your water. When you need more, turn the water on, wait 30 seconds, and then flip the switch back to the "fill" mode. You can (as suggested) also use the initial TDS meter instead of waiting 30 seconds - this is actually a better option. Your TDS meter should have a switch on it that lets you change between probe 1 and 2; 1 should be the input (in the DI resin; output of the membrane), 2 the output of the DI. Note that probe 1 will likely never read 0; it should be low, but will depend upon your water quality, pressure, and other factors. It's also a good idea to know what your normal reading is here since that will be the thing that tells you when your membrane should be replaced (they generally last a year or so, but each system is different).

Not trying to overwhelm you here; so long as you're getting 0 TDS out, then your system is working. Anything more you do is geared towards saving money - not improving water quality.

 

[CoralReefer1019]

Yes; exactly. RO membranes don't work like standard filters that trap particles and just hold them until changed. The membrane traps the particles, but then uses a portion of the water flowing through to flush them out. This is where the quality of the membrane comes into play - the better membranes will be more efficient at this process (removing more material and/or using less water). This is also why you want to have a specific pressure going into your membrane - they process works best at a specific water pressure. You can get a lower quality membrane and/or use pressure that is slightly low or high and it'll still help, but more undesired particles will pass out of the membrane when that's the case. These particles pass into the DI resin, which is depleted faster as a result (read: more cost). The cost of DI resin is generally why it's a good idea to get a quality membrane and ensure that your pressure is correct - even to the point of buying a restrictor and/or buying a booster pump, if needed.
(Note that most membranes available on the market are all made by DOW, so it's really more about buying the right one for your water pressure and flow rate.)



As @Cronicreefer stated above; you'll want to use the valve to force-flush the system at the start (and end, ideally) of a run. Basically; after you finish filling your container, turn the valve the other way (to "flush"), wait 30 seconds, then shut off your water. When you need more, turn the water on, wait 30 seconds, and then flip the switch back to the "fill" mode. You can (as suggested) also use the initial TDS meter instead of waiting 30 seconds - this is actually a better option. Your TDS meter should have a switch on it that lets you change between probe 1 and 2; 1 should be the input (in the DI resin; output of the membrane), 2 the output of the DI. Note that probe 1 will likely never read 0; it should be low, but will depend upon your water quality, pressure, and other factors. It's also a good idea to know what your normal reading is here since that will be the thing that tells you when your membrane should be replaced (they generally last a year or so, but each system is different).

Not trying to overwhelm you here; so long as you're getting 0 TDS out, then your system is working. Anything more you do is geared towards saving money - not improving water quality.

Appreciate the help and helping me figure out everything I now have a better understanding on how my RODI unit works and the components to make it work. I will be leaving it just the way it is and label all the components accordingly.