RO ATO waste water

[seventhz]

Connecting my RO unit to my ATO for the first time and it just dawned on me that my RO unit will continue to produce waste water even when my ATO is not allowing flow of filtered water correct? If so, is there a way around this so that I'm not constantly running water? Will I need to add a shut off valve to the waste line to accomplish this?

 

[RubberFrog]

It will only make waste water during the filtering process.

 

[Jenzifer]

U need a automatic shutoff kit...rubberfrog is correct if u have a shutoff kit...but wrong if u dont have one

 

[James77]

If you have this little gizmo on your filter system, you are all set it will stop all water lines if the water is stopped by a float valve in your top off reservoir. If not it can be easily added in.

http://www.bulkreefsupply.com/store/auto-shut-off-valve.html

 

[zigzag1]

Connecting my RO unit to my ATO for the first time and it just dawned on me that my RO unit will continue to produce waste water even when my ATO is not allowing flow of filtered water correct? If so, is there a way around this so that I'm not constantly running water? Will I need to add a shut off valve to the waste line to accomplish this?

You've heard the other considerable drawbacks and potential problems with using a RO/DI system as the direct source of water for an ATO, correct?

 

[seventhz]

You've heard the other considerable drawbacks and potential problems with using a RO/DI system as the direct source of water for an ATO, correct?

Uuuhhm... apparently not... what are the considerable drawbacks of using ATO water directly from the RO/DI unit?

James77, that's a nifty little device for only 9 bucks. Do you have any experience with it?

 

[James77]

Uuuhhm... apparently not... what are the considerable drawbacks of using ATO water directly from the RO/DI unit?

Haivng an RODI cycle on and off frequently, they are not as effective then. Also, should something go wrong, like the float valve fails, there is an endless supply of water coming in which is a mess. With a contriner you at least limit it. I use a 20 gallon brute in the basement and pump up with a persitaltic pump.

James77, that's a nifty little device for only 9 bucks. Do you have any experience with it?

oh defintely, all of mine have had one. I've never had one fail either. They do need to be replaced every so often, but im on two years with mine and its fine. Now tonight it will probably fail

 

[DHyslop]

Let me elaborate on what Jim's saying about repeated on/off cycles.

The first bit of water the RO membrane produces is dirtier than the rest. If you hook your RO output line directly to a float valve in your sump, it will probably run every day for just a couple minutes, which means every drop your unit produces will be that dirty water.

If you have a holding reservoir for your RO water, you can run the RO unit once a week or once a month but for a longer duration, meaning the vast majority of the water you produce will be good.

In reality it's a little more complex because you likely have a DI stage after the RO which scrubs out a lot of the stuff that makes it through the RO, which means the output water probably is clean. But the more of those on/off cycles you have the faster you burn through that DI resin and the more frequently you have to replace it. There's a lot of people out there who don't even know they need to replace it, either, which means they're producing dirty water all the time.

 

[bdr]

use a holding tank for your top off water and throw a timer on your rodi unit so it can only turn on once a day or once a week to fill your container then it not constantly on

 

[James77]

Thanks for elaborating on that Dhyslop

 

[cordell]

Had my auto shutoff for about 6 years now, still works fine . Most units come with one these days, don't they?

 

[seventhz]

oh defintely, all of mine have had one. I've never had one fail either. They do need to be replaced every so often, but im on two years with mine and its fine. Now tonight it will probably fail

LOL, isn't that always the case

The first bit of water the RO membrane produces is dirtier than the rest.

Good point, I don't know why I didn't think of that because I've noticed that whenever I start my RO/DI unit, the output reading on my TDS meter starts off a bit high and then drops and levels out after about 30 seconds.

Also, should something go wrong, like the float valve fails, there is an endless supply of water coming in which is a mess.

I live in an apartment so I don't even want to think about a part failure resulting in flooding :uhoh2:
Dhyslop, I acquired my RO/DI unit used and I want to say that it's plumbed with the DI cartridge before the RO membrane... is that incorrect plumbing? Should it come after the RO membrane? And this is a bit off the subject but how exactly does the DI resin work? Does it ionically bond to particles?

 

[DHyslop]

LOL, isn't that always the case

Good point, I don't know why I didn't think of that because I've noticed that whenever I start my RO/DI unit, the output reading on my TDS meter starts off a bit high and then drops and levels out after about 30 seconds.

I live in an apartment so I don't even want to think about a part failure resulting in flooding :uhoh2:
Dhyslop, I acquired my RO/DI unit used and I want to say that it's plumbed with the DI cartridge before the RO membrane... is that incorrect plumbing? Should it come after the RO membrane? And this is a bit off the subject but how exactly does the DI resin work? Does it ionically bond to particles?

If you've got a TDS meter on it you're already ahead of the curve.

If you're in an apartment and don't use a lot of water your best bet is just to keep your RODI sitting in a closet somewhere or under the sink and hook it up occasionally to a bucket or bin sitting in the bathtub to make enough water to last you for a while. It's a pain but it's better than having a flood and is kind of the nature of the beast with having a saltwater tank in an apartment. A more permanent installation is usually two large polyethelyne bins or Brute trashcans sitting in a basement with a float valve in one and a pump to move water from one to the other or to mix. On a permanent installation I always have a bulkhead above the level of the float with a pipe that goes to the house drain. Float valves, like all mechanical things, can and do fail occassionally.

The DI stage is basically a tube filled with a mix of two resins. The anion resin has ionic "holes" on its surface that adsorb negative ions onto it, and likewise for the cation resin balls. You use the TDS meter to tell when it's spent. The good TDS meters have dual readings, one before and after the DI. Some DI resins change color from blue to yellow as they become spent. DI can also be chemically regenerated but it's not usually worth it because it really isn't that expensive to begin with. BRS sells the resin and refillable cartridges.

Sometimes it's hard to tell if it's plumbed right if you don't have a lot of experience with them. There should be a hose going from the faucet to the sediment filter, from the sediment filter to the carbon block, from the carbon block to the RO, and two from the RO: one to the drain and one to the DI. From the DI a line should go to the float valve. It's a little more complicated than this because there's probably a shutoff solenoid in there connecting the input and output line of the RO. If you have any doubts about the way it's plumbed take all cartridges out, empty the housings and watch the order with which everything fills with water. Water should usually flow down the sides of the housings and up through the canister.

Good luck!

 

[seventhz]

Hey thanks a lot for the info Dhyslop. When I got the RO/DI unit I replaced the sediment filter, the carbon block, and the DI cartridge, still need to replace the RO membrane though and the dual stage TDS meter was an addition that I made because I just really wanted to be able to see just how efficiently the unit was running and to know whether it was doing it's job or not At the moment I already have the unit under the kitchen sink with input and waste drain tied into all the plumbing and the line running through a couple walls to the DT in the living room, and surprisingly my gf let me do that Just trying to work out the shut-off part at this point.

 

[seventhz]

This may be a really dumb question but what if I were to use two of the shut-off valves that James77 suggested inline with each other so that if one were to fail then the second one would still shut off water flow? Would they still work inline with each other?