RO Auto-Flush Timer Circuit

[pmcustom]

I want to put a couple solonoids on my RO/DI so that whenever I turn the system on, the flush solonoid opens for a couple minutes and then closes. I don't want to run two seperate timers to do this. When I turn the system on (supply solonoid opens) I want a flush solonoid to open for an adjustable amount of time before closing (prob 1 or 2 min). Then the system would have to reset when the supply solonoid is cycled (closed, then back on). Can anyone provide a schematic for this setup? Thanks.

[Donw]

Are you just trying to automate the membrane flush/restrictor bypass. Where does the rodi outlet go (float valve ,solenoid?)?

Don

[pmcustom]

I'm trying to automatically flush the membrane, but I also want to drain the RO output (before the DI) during the flush. High-TDS water still leaves the "clean" RO output during the flush, just at a reduced rate. I would like to keep that from going through the DI and using it up faster...or do you think it's not enough to worry about? The TDS shoots up to as much as 80 or more during startup, if it's been off for a while. Do you think it's enough to worry about?

[Donw]

<a href=showthread.php?s=&postid=8400055#post8400055 target=_blank>Originally posted</a> by pmcustom
I'm trying to automatically flush the membrane, but I also want to drain the RO output (before the DI) during the flush. High-TDS water still leaves the "clean" RO output during the flush, just at a reduced rate. I would like to keep that from going through the DI and using it up faster...or do you think it's not enough to worry about? The TDS shoots up to as much as 80 or more during startup, if it's been off for a while. Do you think it's enough to worry about?

I would definatly bypass the DI. How you go about this will depend on what your outlet is connected to or not connected normally. If it goes to a solenoid or float valve youve got it made.

Don

[pmcustom]

It goes to a float valve, but I don't see how that helps because whenever I'd be turning on the RO/DI, the float would be open. So you think the small amount of high-tds water that leaves the RO should be kept from the DI? That was my original plan, but it would require 4 solenoids and the timing circuit mentioned above, which would be farily costly. If it could be avoided, it would be nice.

[Donw]

<a href=showthread.php?s=&postid=8400240#post8400240 target=_blank>Originally posted</a> by pmcustom
It goes to a float valve, but I don't see how that helps because whenever I'd be turning on the RO/DI, the float would be open. So you think the small amount of high-tds water that leaves the RO should be kept from the DI? That was my original plan, but it would require 4 solenoids and the timing circuit mentioned above, which would be farily costly. If it could be avoided, it would be nice.

You want the flush to occure just before the float valve opens. You dont need to do a membrane flush but what I call a ro dump. Either way its up to you. I assume this goes to a ato controlled by a float sw and pump. If this is the case then this logic sequence will work and no timer is needed just 2 solenoids and some wire. If not then I'll need mor info.

If ato is turns ON
Then rodi flush is ON
If ato turns Off
Then rodi flush is Off
and rodi is refilling tank and will shut down with the float valve.

Make sense?

Don

[pmcustom]

no, i just have a float valve in a bucket. the ato is a float valve which is gravity fed by the bucket. so all the rodi fills is the bucket and a water change reservoir, which both have float valves. i have no float switches anywhere...everything is mechanical now. what i need, regardless of how i decide to set it up, is a circuit that, when powered, opens the ro water supply solenoid and a flush solonoid for a couple minutes before removing power from the flush solenoid. when power is removed (by a single timer) the whole thing would reset for another cycle. keep in mind, the ro/di is not being used as an ato, just to fill a couple reservoirs through float valves.

[Donw]

<a href=showthread.php?s=&postid=8400419#post8400419 target=_blank>Originally posted</a> by pmcustom
no, i just have a float valve in a bucket. the ato is a float valve which is gravity fed by the bucket. so all the rodi fills is the bucket and a water change reservoir, which both have float valves. i have no float switches anywhere...everything is mechanical now. what i need, regardless of how i decide to set it up, is a circuit that, when powered, opens the ro water supply solenoid and a flush solonoid for a couple minutes before removing power from the flush solenoid. when power is removed (by a single timer) the whole thing would reset for another cycle. keep in mind, the ro/di is not being used as an ato, just to fill a couple reservoirs through float valves.

Do you want this to happen by itself by each time the float valve opens? Or do you want to push a button and have it happen?

Don

[BruiseAndy]

pretty simple circuit one timer, one SPST relay, and two solenoids. You would wire the flush solenoid to the normally closed contacts.
I would suggest using a ATO as the signal source as it would be one less thing to worry about. I also usally like piping two solenoids in series and wiring them in paralell. Saves you if one fails.

http://members.aol.com/andybg8000/schematicm.jpg

[Donw]

<a href=showthread.php?s=&postid=8400684#post8400684 target=_blank>Originally posted</a> by BruiseAndy
pretty simple circuit one timer, one SPST relay, and two solenoids. You would wire the flush solenoid to the normally closed contacts.
I would suggest using a ATO as the signal source as it would be one less thing to worry about. I also usally like piping two solenoids in series and wiring them in paralell. Saves you if one fails.

http://members.aol.com/andybg8000/schematicm.jpg

Ato is manual so no signal to be used. Ato is a float valve so valve needs to be off for two solenoids to work.

Don

[BruiseAndy]

Ato is manual so no signal to be used. Ato is a float valve so valve needs to be off for two solenoids to work.

Don


Exactly why I suggested he integrate an automatic top off (ATO) system, if not it's a simple as using a $5 float switch and $5 transformer for signal as long as relay coil corresponds with transformer voltage.

[Donw]

<a href=showthread.php?s=&postid=8400883#post8400883 target=_blank>Originally posted</a> by BruiseAndy
Exactly why I suggested he integrate an automatic top off (ATO) system, if not it's a simple as using a $5 float switch and $5 transformer for signal as long as relay coil corresponds with transformer voltage.

He didnt seem to like that Idea, I already questioned it above, no timer would be needed if he had a electronic ato.

Don

[pmcustom]

I don't want to integrate float switches into the ato system...i like what i have. i just want a stand-alone system for the ro/di, regardless of what it's filling. either way, i'm just trying to get ideas now. so can anyone come up with a ciruit like i described?

[Donw]

<a href=showthread.php?s=&postid=8401006#post8401006 target=_blank>Originally posted</a> by pmcustom
I don't want to integrate float switches into the ato system...i like what i have. i just want a stand-alone system for the ro/di, regardless of what it's filling. either way, i'm just trying to get ideas now. so can anyone come up with a ciruit like i described?

It would be simple if you would tell us how you want to trigger it, manual or automatic.

Don

[pmcustom]

forget about what the ro/di is going to, or the sump ato, or anything else. it doesn't matter what the ro/di is feeding. i want a stand-alone system for the ro/di that, when given power (by a timer or whatever), the supply solenoid opens until the power is shut off (this is the easy part), but the flush solenoid only opens for the first couple minutes (the hard part...it would shut off even though the power is still there). i would think this would require some kind of timer ic and a transistor and/or latching relay, but i don't have the knowledge to design the circuit myself. thanks.

[BruiseAndy]

<a href=showthread.php?s=&postid=8400419#post8400419 target=_blank>Originally posted</a> by pmcustom
what i need, regardless of how i decide to set it up, is a circuit that, when powered, opens the ro water supply solenoid and a flush solonoid for a couple minutes before removing power from the flush solenoid. when power is removed (by a single timer) the whole thing would reset for another cycle. keep in mind, the ro/di is not being used as an ato, just to fill a couple reservoirs through float valves.

OK reread more closely and here is what you are asking for

http://members.aol.com/andybg8000/schematicn.jpg

you can find the timers on ebay for pretty cheap (omron and icm are two to look for).

The signal source is up to you.

edit:

http://cgi.ebay.com/New-HVAC-Air-Conditioner-Sequencer-On-1-110-Off-1-110_W0QQitemZ290040629455QQihZ019QQcategoryZ42911QQssPageNameZWDVWQQrdZ1QQcmdZViewItem?hash=item2900 40629455

This sequencer would work well for you if you were using 24VAC, you can also find electric heat sequencers in different timings or adjustable timings.

[pmcustom]

I get it, but it's using two timers (since my signal is going to be a timer), and that's what I'm trying to avoid.

[BruiseAndy]

So do you not care what other components are in the system as long as you only have one timer (within reason).

edit:

Sent you a PM with an ebay auction of the timer you need.

That will do what you want without having to wire any relays or anything. It's what I use to control lighting

[BeanAnimal]

Perfect job for an 8 PIN PIC :)