Auto run RO container fill

[Redman88]

So I know I have hard water so a preflush of the RO membrane is a must and something I have been doing. So I want to automate my RO container fill and flush the membrane before I start filling my containers. Most of the auto shutoffs don't flush and the ones that do are for industrial systems so the price is outside of my range. This auto fill/flush system is going to use 5 solenoid valves at least one time delay relay, and a manual override switch. Nothing drawn up yet but I will update. Yes I could do some kind of micro controller but I am not that good at programming and learning what I needed would take longer then I am willing to wait. I also still need to run a dedicated circuit out to my porch where my water change/ RO containers are.

 

[abelavin]

Please, describe that you want from automatic system. I think, 3 solenoid NC valve its enough for flush membrane, drain "dirty" ro water and filling tank. I make system, like you want, for my friend one month ago. Its not expensive by components.

 

[Redman88]

going with 4 because the system isn't just for flush it also turns on the water to fill my RO containers. after looking at it i can drop from 5 to 4 for this project.

dimonds 1, 3 turn on to flush the membrane while 4 stays closed. 2 turns on to provide water to the whole system

 

[Redman88]

okay so i have put together a very simple block diagram for the wiring of this setup

 

[abelavin]

I take some time to understand photo... Thank you for this explanation.
And sorry about my bad english...

 

[abelavin]

Are you planing use DI cartridge?

 

[Redman88]

Yes there will be a DI stage that is the point of the valves after the membrane to flush to waste and not exhaust the DI.

 

[abelavin]

 

[abelavin]

Valve one - flush membraine. This is first stage of program cycle. 1-5 min.
Valve two - flush RO tails. Second stage. 5-10 min.
Valve three - feeding tank RO pure water. Stage wait until float sensor is ON, or wait 1-5 hours for filling tank.
Stage four - waiting for empty tank or 5-10 hours for evaporation from aqua.
Stage five - go to stage one.

 

[abelavin]

Now under constraction my new version of "Osmosis Manager".
On photo hardware prototype.

 

[Redman88]

the only problem i have with the placement of #2 on yours is you are not going to be able to flush the clean side of the membrane due to back pressure from flushing the input side.

 

[abelavin]

Why not? First valve open, clean membrane and close. Then second valve open, flush tails to drain in normal mode of RO membrane, then close.
Next - valve 3 open, and filling tank begin.
One point - for good flushing RO membrane need stay closed valves 2 and 3 then valve 1 start to open for flush. This is give back hydraulic impulse for cleaning membraine.

 

[Redman88]

well i haven't seen or found any info regarding the need to prevent out flow from the product line during flush. but i know i don't want the little that does come out during flush to make it to my DI so I am going to set mine up to flow to waste during flush. Stay tuned i am working on a proper wiring diagram for inspection and comment.

 

[Redman88]

okay here it is, Auto Flush and fill for an RO container.

S2 is the low limit switch on the ATO and S1 is the upper limit, the dual switches allow for a latch to keep everything running till the container fills up
the upper contacts on RY2 is for the booster pump for the RO system
RY1 is a time delay relay though that is the wrong symbol for it when it receives power it switches power to L1 and L3 to flush the RO membrane
after the preset time RY2 releases and L4 receives power and starts to produce water
L2 opens as soon as the ATO portion is complete

 

[Redman88]

Okay no questions concerns or criticisms of my design?

 

[abelavin]

Please, write functionality on ich valve and relay. For better explanation.
For my opinion, need analysing multi on/off contact bounce, which was generate from rippling water from limit switches. Need make separate flushing time(L1) on membraine and flushing "tails" (L3) after membrane.

 

[abelavin]

And, don't forget add some protected circuit to overfilling. Float switches is not absolutely reliability.

 

[Redman88]

Please, write functionality on ich valve and relay. For better explanation.
For my opinion, need analysing multi on/off contact bounce, which was generate from rippling water from limit switches. Need make separate flushing time(L1) on membraine and flushing "tails" (L3) after membrane.

Rippling water will only matter on S2 and the effect will be to turn the system off early but that is the point of the two switches a set distance apart vertically. So the system is not constantly turning on and off.

 

[Redman88]

And, don't forget add some protected circuit to overfilling. Float switches is not absolutely reliability.

Over flow protection will be a float valve.

 

[abelavin]

Ok. Yours design is fine.
But, I'm not sure about L1 and L3 working together in same time. For clean "tiles" from membrane need flush 5-10 liters RO water in drain. For clean membrane need only 1 min to open restrictor flow to drain.
My design use separate timer interval for it and use floater water valve as main shut off unit. Fot overfiling may use one small floater switch or smart overfilling protector for RO units(see on picture below). In this case you dont need to use any wires and electric components in RO tank.