RO/DI waste water and auto shut off question

C

chbix

Reefing newb
Ok so in my previous water quality post its apparent that my used 12GPD RO unit was a waste of cash, thankfully only $20, and I have to get a new one anyway.

So research has shown that for every gallon of water im wasting about 3-4 gallons. So what im thinking about doing is having the RO unit mounted in my garage and have two 55 gallon drums, one for the good water and one for the waste water. I want to set up an auto shut off so I dont have to watch it. So obviously common sense would state that the auto shut off should go on the waste water tank because it fills up 3-4 times faster than the good water. Should I also put an auto shut off on the good water too?

What do you guys do with your waste water? I dont want to simply send it down a drain cause thats wasting water and its expensive. My thought is to store it and use if for watering plants, etc.

Is the waste water bad? I mean obviously its called waste water but are their bad chemicals that are released into through the ro process? My other idea was to set up some kind of system where the waste water goes out and fills up the bucket my dogs drink out of. But then that would need an auto shut off and my dogs would eat that up. Any ideas for making a shut off valve bullet proof so my dogs cant eat it?

Would it be bad to leave the RO unit outside?

Thanks guys I know its alot of questions in one post.
 
Never mind on the outside question, that wont work, i forgot it gets below freezing here in the winter so that definately wont work outside.
 
The way i see it is you'd have to control waste water and RO water separately each with it's own shut off. I guess you could have a main shut off that shuts of the entire unit when the RO container is filled. But then for the waste you would need to split the waste line with one line going to the waste container and a second line going outside or to a drain. Somehow set it up with the shut off valve in the waste container so that when it's tripped, water is then forced to head out the other line to the drain or outside.
 
A lot of people use the waste water for doing laundry or watering plants. I wouldn't give it to the pets -- basically all the salts, metals and solids in tap water get concentrated in it. I'd be worried about it creating some sort of ionic imbalance in the dogs. But it's fine for cleaning and the yard. Some people here have it hooked up directly to their washer.
 
You just need a couple float switches and some relays to do it. Use latching relays.

Put a high water float switch in the waste water tank. This switch will turn the power for the pump ON and OFF.

Pump water out of the RO storage tank into your sump for auto top-off.

Put 2 float switches in the sump. Latching relays on each switch. Mount one exactly where you want the water level to remain during normal operation. Mount the other 1/2 inch below it. Now you are essentially using 2 float switches like one long-stroke float. The first float - normal level float - will simply complete the circuit. The lower switch will drop when enough water evaporates and this will energize and lock the relay. That will trigger your RO storage tank pump to fill the sump. When the top float goes back up - switch is opened and pump shuts down to prevent over-filling of sump. I'd recommend solenoid valves - because a 50g storage tank is going to have enough head pressure to blow past any pump and fill your sump to the point of overflowing. Simply put a 12v solenoid valve (yes, you can buy plastic valves) in the line between the RO storage tank and the sump you intend to keep at a specific level. Lower float drops, solenoid valve opens , pump turns on and tops off sump. Upper float switch in sump goes back up - solenoid valve closes, pump shuts off.

To put the waste water into your washing machine, simply install a demand pump. Like a well pump. It will keep water pressure on the washing machine all the time. Your washing machine has internal shut off valves, so it's normal for it to deal with high water pressure. Connect the well water pump to your waste water tank. Now wash clothes as normal. You can install a Y-line from the house water line and use solenoids to control where the washing machine fills from. It should normally fill from the waste water tank. But in the event the waste water tank is empty - there should be a lower float to trip the solenoid valves. The waste water valve shuts off and the house water valve opens and bypasses the well pump. This way you can wash clothes anytime you want, instead of only when the waste water tank is full.

It's all pretty easy to do with some float switches and latching relays. You'll need a few 12v solenoid valves and a couple 12v power supplies.
 
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That sounds way more complicated than what I had visioned but now its got my creative engineering blood flowing.... i would love to do an auto topoff, but the location of the tank relative to water sources just dont make that possible. I will have to figure out some more things and see what works best for my application, thanks for the input!
 
I'm in the same boat as you. My kitchen sink (where my RODI unit is) is very far from my tank. To top off, I just fill a 5-gallon bucket every night (set the oven timer so I don't forget and flood the kitchen), go do my stuff, come back, and top off the tank. I used to have an auto-top off system in my old house, but the location of the RODI unit relative to my tank made it possible. Now, not so much.
 
Bifferwine said:
I'm in the same boat as you. My kitchen sink (where my RODI unit is) is very far from my tank. To top off, I just fill a 5-gallon bucket every night (set the oven timer so I don't forget and flood the kitchen), go do my stuff, come back, and top off the tank. I used to have an auto-top off system in my old house, but the location of the RODI unit relative to my tank made it possible. Now, not so much.
Click to expand...

Hey biff, why didnt you hook up the auto top off to the 5 gallon bucket? That way you wouldnt have to set the timer or worry about a flood?
 
I don't know... It's easier to just set the oven timer. And I keep the bucket in the closet when I'm not using it, so it doesn't stay in the kitchen all the time.
 
Sorry, I did not get to hook it up to my washer. I did want to though :D Problem is, my rodi is in the basement, while my washer is in the 3rd floor. I would have wanted a way to hook it up to my toilet as well.

We're always trying to find a way. The only way I can think of is to hook up a really powerful pump to pump the dirty water up to a large bin to the 3rd floor. Maybe I will one day.
 
You could a line from the bottom of your waste water out to your trees or whatever you wanted watered, and it would always just keep a little water headed out to them. Then you would only need the float valve to shut off when your good water fills up.

My RODI is under the sink in the kitchen. There is a line that goes up the wall and over to the fridge across the kitchen. So I just put a T on that line, took it into the attic and ran it over above my tank, dropped in down to the tank and put a valve on the end, so I open it to fill the tank, and close it when I don't need any water. Might do something like that Biff...just some 1/4" hose up the wall into the attic off your unit under sink and take it anywhere you want in the house.
 
cottonwood just made me think that my fridge is closer to my tank than the water supply and I have a line running to my fridge for the ice maker. Maybe I can piggy back that as the water source for my RO unit? is there enough flow/pressure? I cant go in the attic, well I can but its no good cause I have a 2 story house and the tank will be on the first floor. I thought about running the waste water line to a drip system for the plants out front but not sure how well that would work and would only work during the summer as it gets below freezing here.
 
I have mine just T'd off from my line that goes to the fridge and there is plenty...the fridge barely uses any and when I have the line open that goes to my tank it has all the flow and will use whatever my system can produce. I just cant try to have water from both at the same time. The unit at my place was done before I moved in, so I'm pretty sure the waste water goes down the drain. I didn't know it wasted that much!
 

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