RODI solenoid valve placement

[Joe Batt]

I have set up an Apex FMM with two optical sensors in my RODI water tank. One low sensor to turn on the RODI unit via a solenoid valve and one high sensor to turn off the RODI via a solenoid. The reasoning behind the plan is to try and prevent TDS creep by using the RODI water tank as a water ‘capacitor’ that only fills when the water tank is low. I also have a float valve for backup for the full sensor failure case, and intend to time the fill and implement that as an additional fail safe.

Where is the best location for the RODI solenoid? On the water input to the RODI or on the output from the RODI to the water tank? Please also state your reasoning.

 

[Michael Lane]

I have mine set up with the soleniod on the input to the RODI. The soleniod valve I'm using requires pressure in order to stay closed, so it would not work properly on the output side. It also makes it convenient when I change filters. When the valve is closed, the RODI isn't pressurized and I can change everything out with minimal mess.

 

[KStatefan]

Mine is on the output of DI.

 

[TheHarold]

It totally depends on how you have the RODI set up. If you have auto shut off, you can put it on the output. That way you can also use the float valve for redundancy, to shut off the RODI when full.

Without the auto shut off, you would need it on the supply line.

 

[Joe Batt]

It totally depends on how you have the RODI set up. If you have auto shut off, you can put it on the output. That way you can also use the float valve for redundancy, to shut off the RODI when full.

Without the auto shut off, you would need it on the supply line.

I have auto shutoff of the water via a solenoid that will trip closed when the high sensor trips. There is a float backup for the overfull case that shuts off the supply output from RODI should the high optical sensor fail

 

[Brett S]

I actually have solenoids on both the input and output sides of my RODI. The one on the input will turn the whole RODI system on and off and I think it’s good to have it on the input side because that will ensure that system is depressurized when it’s off. I think it’s a little better for the RODI filter that way and if the filter were to pop a hose or spring a leak for some reason then it wouldn’t run indefinitely. If you were only going to use one, then I would say input side.

My RODI output is split with a T and one side leads to my AWC reservoir and the other leads to my ATO reservoir. Each side has their own solenoid valve so the Apex can fill whichever reservoir need to be filled. But even if you don’t need to split the output I think there is value in having a solenoid on both sides. This way even if one solenoid were to fail I wouldn’t have a flood since the other would still be operating. (Although I’ve been using the same solenoids for more than three years now without a single failure).

Finally, I also have a mechanical float valve on the line that fills each reservoir as an additional backup. Even if both solenoids were to fail or something happened with the apex and the RODI was left on the mechanical valve would shut off the flow and prevent a flood. I also have the apex leak detector with a sensor on the floor near my reservoirs, so if something does leak or overflow the apex will automatically shut off the water and alert me.

Like I said, I’ve been running it this way for more than three years and it’s been working great. I also have a water level sensor at the top and bottom of each reservoir and the apex will start the RODI to fill the reservoir when the water level hits the lower sensor, then it will turn off the RODI when it hits the the top sensor. Let me know if you want to see the apex programming that I use for this.

 

[Joe Batt]

I actually have solenoids on both the input and output sides of my RODI. The one on the input will turn the whole RODI system on and off and I think it’s good to have it on the input side because that will ensure that system is depressurized when it’s off. I think it’s a little better for the RODI filter that way and if the filter were to pop a hose or spring a leak for some reason then it wouldn’t run indefinitely. If you were only going to use one, then I would say input side.

My RODI output is split with a T and one side leads to my AWC reservoir and the other leads to my ATO reservoir. Each side has their own solenoid valve so the Apex can fill whichever reservoir need to be filled. But even if you don’t need to split the output I think there is value in having a solenoid on both sides. This way even if one solenoid were to fail I wouldn’t have a flood since the other would still be operating. (Although I’ve been using the same solenoids for more than three years now without a single failure).

Finally, I also have a mechanical float valve on the line that fills each reservoir as an additional backup. Even if both solenoids were to fail or something happened with the apex and the RODI was left on the mechanical valve would shut off the flow and prevent a flood. I also have the apex leak detector with a sensor on the floor near my reservoirs, so if something does leak or overflow the apex will automatically shut off the water and alert me.

Like I said, I’ve been running it this way for more than three years and it’s been working great. I also have a water level sensor at the top and bottom of each reservoir and the apex will start the RODI to fill the reservoir when the water level hits the lower sensor, then it will turn off the RODI when it hits the the top sensor. Let me know if you want to see the apex programming that I use for this.

Sounds very similar to what I am doing but just with one water barrel being filled. I like the dual solenoid idea. I would appreciate seeming your coding, thank you very much.

 

[Brett S]

No problem. The program for solenoid on the output that controls the ATO reservoir looks like this:

RODI_ATO:
Fallback OFF
If ATO_L CLOSED Then ON
If ATO_H CLOSED Then OFF
If Fld_GF CLOSED Then OFF

ATO_L is the low water level sensor in the ATO reservoir and ATO_H is the high water sensor. Fld_GF is the garage floor flood sensor that is near the water reservoirs, so if that gets closed then it means there’s water on the garage floor, so the apex shuts off the RODI.

Also, note that there is no SET command in this program. It’s kind of unusual that way, but skipping the SET command means that it will remember what state it’s in and it will only change the state if one of the IF commands is true. This is the magic that allows it to turn on the RODI when the water level hits the low level sensor, then leave it on until it hits the high level sensor, even when the low level sensor is OPEN again.

The program for the solenoid for the RODI input looks like this:

RODI:
Fallback OFF
Set OFF
If Output RODI_ATO = ON Then ON
If Output RODI_NSW = ON Then ON
If Fld_GF CLOSED Then OFF

RODI_ATO is the ATO output solenoid that I talked about above and RODI_NSW is the solenoid for the NWS reservoir for my ATO. This program is pretty straightforward and if either of those are turned on, then the RODI input solenoid also gets turned on. And again, if the garage floor flood sensor is detecting water then the apex closes this solenoid.

 

[Joe Batt]

Thank you, The If ATO_L CLOSED Then ON takes a little thinking about but think I understand. I am wanting to put in a timer as well as another safety point. It takes 120 mins for the RODI to fill the container between the Lo switch and the Hi.

I was looking along the lines of

Fallback OFF
If Ro-Wlo OPEN Then ON
If Ro-WHi CLOSED Then OFF
Min Time 120:00 Then ON

 

[Brett S]

The above is all you need for just the ATO, but for the sake of completeness I’ll include my programming for the AWC reservoir as well. I’m putting it in a separate post to try to avoid confusion as none of this is necessary just for ATO.

The program for the solenoid that controls the ATO reservoir looks about the same as the one for the ATO reservoir:

RODI_NSW:
Fallback OFF
If NSW_L CLOSED Then ON
If NSW_H CLOSED Then OFF
If Fld_GF CLOSED Then OFF

Again, no SET command and NSW_L and NSW_H are the low and high level sensors in the NSW reservoir.

However, there is a bit of additional programming to help control my AWC system. Obviously I don’t want the AWC to continue running while the reservoir is filling or before I’ve added salt to it. So I have two virtual outlets called MAKE_NSW and MAKE_NWS_RST which looks like this:

MAKE_NSW:
Set ON
If Output Make_NSW_Rst = ON Then OFF
If NSW_L CLOSED Then ON

MAKE_NSW_RST:
Set ON
If Output Make_NSW = ON Then OFF

These are a bit weird looking, but they work like this: MAKE_NSW is just a flag that indicates to the system when I’m in the process of making new sea water. MAKE_NSW is normally OFF. It gets turned ON when the low water level sensor in the NSW reservoir is triggered. This is when the apex starts refilling that reservoir. My AWC system will automatically turn OFF when MAKE_NSW is turned on because the reservoir is getting filled with freshwater and I don’t want to be doing water changes again until the reservoir is full and the salt has been added and mixed in.

MAKE_NSW_RST is a virtual outlet that is normally ON, which holds the MAKE_NSW outlet in the normal OFF state. However, as soon as the system starts refilling the NSW reservoir then MAKE_NSW turns on and this forces MAKE_NSW_RST to off. This allows the MAKE_NSW outlet to stay ON indefinitely. I don’t want it to turn OFF until after I have added salt to the water, allowed it to mix, and verified the salinity.

The apex email alarm is also configured to email me when MAKE_NSW turns ON so this way I know that I will need to add salt to the water. I also have a power head in the bottom of the NSW reservoir what runs for a few minutes several times a day to circulate the water in the reservoir. However, when MAKE_NSW turns ON the power head also comes ON and stays ON so that it will help mix in the salt when I add it.

Finally, once the reservoir has been filled, the salt has been added and allowed to mix in and I verified the salinity then I will manually turn MAKE_NSW_RST to ON for a few seconds, then switch it back to AUTO. This resets the MAKE_NSW outlet back to OFF which in turn restarts the AWC system.

 

[Brett S]

Thank you, The If ATO_L CLOSED Then ON takes a little thinking about but think I understand. I am wanting to put in a timer as well as another safety point. It takes 120 mins for the RODI to fill the container between the Lo switch and the Hi.

Again, ATO_L is my low level sensor in the ATO reservoir. It’s normal state is OPEN, so when there is water in the reservoir it is OPEN. As soon as the water level drops down below the sensor, then the sensor switches to CLOSED.

So “If ATO_L CLOSED Then ON” simply turns on the solenoid when the water level drops below the level of the sensor. If your sensor is normally CLOSED and becomes OPEN when the water level drops you would simply change that to “If ATO_L OPEN Then ON”

As far as the timer goes you could simply add the following line at the end of the program:

When ON > 120:00 Then OFF

That forces the outlet to OFF if it is ON for more than 120 minutes. Note that this is a special command that actually takes it out of AUTO and forces it into manual OFF and it will need to be manually reset to AUTO before it will start working again. Also, note that by default there is no alert that this happened, so you might not notice until your ATO reservoir runs dry.

To get alerted if the timer forces the outlet to off you can add the following command to your email alarm program:

If Error RODI_ATO Then ON

This will send you a notification when the timer forces the outlet to OFF and puts it in an Error state.

 

[Shunopoli]

The above is all you need for just the ATO, but for the sake of completeness I’ll include my programming for the AWC reservoir as well. I’m putting it in a separate post to try to avoid confusion as none of this is necessary just for ATO.

The program for the solenoid that controls the ATO reservoir looks about the same as the one for the ATO reservoir:

RODI_NSW:
Fallback OFF
If NSW_L CLOSED Then ON
If NSW_H CLOSED Then OFF
If Fld_GF CLOSED Then OFF

Again, no SET command and NSW_L and NSW_H are the low and high level sensors in the NSW reservoir.

However, there is a bit of additional programming to help control my AWC system. Obviously I don’t want the AWC to continue running while the reservoir is filling or before I’ve added salt to it. So I have two virtual outlets called MAKE_NSW and MAKE_NWS_RST which looks like this:

MAKE_NSW:
Set ON
If Output Make_NSW_Rst = ON Then OFF
If NSW_L CLOSED Then ON

MAKE_NSW_RST:
Set ON
If Output Make_NSW = ON Then OFF

These are a bit weird looking, but they work like this: MAKE_NSW is just a flag that indicates to the system when I’m in the process of making new sea water. MAKE_NSW is normally OFF. It gets turned ON when the low water level sensor in the NSW reservoir is triggered. This is when the apex starts refilling that reservoir. My AWC system will automatically turn OFF when MAKE_NSW is turned on because the reservoir is getting filled with freshwater and I don’t want to be doing water changes again until the reservoir is full and the salt has been added and mixed in.

MAKE_NSW_RST is a virtual outlet that is normally ON, which holds the MAKE_NSW outlet in the normal OFF state. However, as soon as the system starts refilling the NSW reservoir then MAKE_NSW turns on and this forces MAKE_NSW_RST to off. This allows the MAKE_NSW outlet to stay ON indefinitely. I don’t want it to turn OFF until after I have added salt to the water, allowed it to mix, and verified the salinity.

The apex email alarm is also configured to email me when MAKE_NSW turns ON so this way I know that I will need to add salt to the water. I also have a power head in the bottom of the NSW reservoir what runs for a few minutes several times a day to circulate the water in the reservoir. However, when MAKE_NSW turns ON the power head also comes ON and stays ON so that it will help mix in the salt when I add it.

Finally, once the reservoir has been filled, the salt has been added and allowed to mix in and I verified the salinity then I will manually turn MAKE_NSW_RST to ON for a few seconds, then switch it back to AUTO. This resets the MAKE_NSW outlet back to OFF which in turn restarts the AWC system.

Are you using the DOS for AWC? If so do you have any additional code other than the automatic setup for the awc with the dos that includes your MAKE_NSW code. If so can you provide. I am trying to setup your exact setup with mine. This is exactly what I want. I want my RODI to go directly to my ATO container in my Display cabinet(controlled with high low sensor) In my sump I have the ATK feeding from ATO. I then will have the RODI feeding my SW container also, I will then want my DOS to do my auto water change from this container.

 

[Brett S]

Are you using the DOS for AWC? If so do you have any additional code other than the automatic setup for the awc with the dos that includes your MAKE_NSW code. If so can you provide. I am trying to setup your exact setup with mine. This is exactly what I want. I want my RODI to go directly to my ATO container in my Display cabinet(controlled with high low sensor) In my sump I have the ATK feeding from ATO. I then will have the RODI feeding my SW container also, I will then want my DOS to do my auto water change from this container.

I am using the DOS for AWC. I just set it up with the wizard, but then I went into the the advanced setup and under the tdata line I added the following:

IF Output MAKE_NSW = ON Then OFF

That makes sure that the AWC doesn’t run while the NSW reservoir is filling and before salt has been added to the new water.

 

[Shunopoli]

I am using the DOS for AWC. I just set it up with the wizard, but then I went into the the advanced setup and under the tdata line I added the following:

IF Output MAKE_NSW = ON Then OFF

That makes sure that the AWC doesn’t run while the NSW reservoir is filling and before salt has been added to the new water.

Awesome I have my dos coming soon along with my optical sensors and solanoids and am going to try and do your exact setup. I might ping you if I have questions. Make_nsw is manually triggered? I’m just trying to understand how everything runs, but stops in time for you to mix salt

 

[Brett S]

Awesome I have my dos coming soon along with my optical sensors and solanoids and am going to try and do your exact setup. I might ping you if I have questions. Make_nsw is manually triggered? I’m just trying to understand how everything runs, but stops in time for you to mix salt

Make_nsw is automatically triggered when the low level sensor in the nsw reservoir triggers. That stops the AWC while the reservoir fills. Once the reservoir has filled and salt is added then it needs to be manually reset to start the AWC again.

And feel free to reach out. You’ll probably have better luck sending me a PM since that will also email me. Life has been a little crazy lately and I haven’t had much time to be active on the forum, so I might miss a reply to a thread.

I actually remember going through and posting all of the logic and programming I used to get all of this to work somewhere, but I can’t remember when or where I posted it. I’ll try to see if I can find that post. Otherwise maybe I just need to post it again.

 

[Shunopoli]

Make_nsw is automatically triggered when the low level sensor in the nsw reservoir triggers. That stops the AWC while the reservoir fills. Once the reservoir has filled and salt is added then it needs to be manually reset to start the AWC again.

And feel free to reach out. You’ll probably have better luck sending me a PM since that will also email me. Life has been a little crazy lately and I haven’t had much time to be active on the forum, so I might miss a reply to a thread.

I actually remember going through and posting all of the logic and programming I used to get all of this to work somewhere, but I can’t remember when or where I posted it. I’ll try to see if I can find that post. Otherwise maybe I just need to post it again.

It’s on this thread. I will re-read it

 

[Shunopoli]

Finally, once the reservoir has been filled, the salt has been added and allowed to mix in and I verified the salinity then I will manually turn MAKE_NSW_RST to ON for a few seconds, then switch it back to AUTO. This resets the MAKE_NSW outlet back to OFF which in turn restarts the AWC system.
[/QUOTE]

Can you explain why you turn on MAKE_NSW_RS to on for a seconds? What does that few seconds accomplish before switching it o auto?

 

[Brett S]

It’s on this thread. I will re-read it

Oh, lol. I guess I didn’t have to look far to find it then.

 

[Brett S]

Can you explain why you turn on MAKE_NSW_RS to on for a seconds? What does that few seconds accomplish before switching it o auto?

MAKE_NSW and MAKE_NSW_RST interact with each other and it gets a little confusing (ok, maybe a lot confusing)

MAKE_NSW is set to on by default, which means that it is in making saltwater mode, so either the reservoir is refilling or it’s waiting for salt to be added. As we discussed above. This also turns off the AWC. Here is the MAKE_NSW program:

MAKE_NSW:
Set ON
If Output Make_NSW_Rst = ON Then OFF
If NSW_L CLOSED Then ON

The second line will turn MAKE_NSW off if MAKE_NSW_RST is turned on. When MAKE_NSW is off then it is no longer in the making saltwater mode and it knows that there is saltwater in the reservoir, so the AWC will be turned on and run.

The third line will turn MAKE_NSW back on automatically when the low level float switch in the reservoir is triggered. This is how it knows that it is out of saltwater and it starts the whole process over again.

Separately, the program for RODI_NSW will automatically refill the reservoir when the low level switch is triggered.

Now, here is the program for MAKE_NSW_RST:

MAKE_NSW_RST:
Set ON
If Output Make_NSW = ON Then OFF

By default it is on which, as we discussed above, causes MAKE_NSW to be off (think of that as the making saltwater mode being off).

However, the second line here will turn MAKE_NSW_RST off when MAKE_NSW is on. So when it is in the making saltwater mode then MAKE_NSW_RST goes off.

At this point they are locked in this state. Once MAKE_NSW gets turned on the only way for it to turn off is for MAKE_NSW_RST to be on. However, the only way for MAKE_NSW_RST to automatically be on is if MAKE_NSW is off.

The reason they need to get into this locked state is to ensure that they can only be manually reset. We don’t want the AWC to start again while the reservoir is refilling or before salt has been added to the reservoir.

So, the way to get them out of this locked state and let the AWC start again is to manually turn MAKE_NSW_RST on. Once that happens MAKE_NSW will turn off (because of the second line in that program) and the system will be out of making saltwater mode. At this point you can switch MAKE_NSW_RST back to auto. Since MAKE_NSW is now off, the second line in the MAKE_NSW_RST program wont trigger, and MAKE_NSW_RST will stay on.

They will now be locked in this state until the low level float switch triggers again and starts the whole process over.

Hopefully that made sense and didn’t make your brain hurt too much. It’s definitely rather confusing because of the way they interact. Let me know if you still have other questions.

 

[Erick Armanii]

Wow