Turning two individual softeners into integrated twin tank system.

[Hatsuwr]

Hi everyone,

I've been looking around for a twin tank control valve that does upflow regeneration, soft water brine tank refill, soft water regeneration, and which has no hard water bypass. Pretty sure that doesn't exist. (Please let me know if it does!)

So, I figured I'd see if I could rig something up. Here's my solution: 2x Fleck 5800 control valves, 2x check valves, and 4x normally-open solenoid valves.

Red is the normal raw water inlet.
Blue is the normal soft water outlet.
Green is for the crossover.
Grey vertical components are check valves that only allow flow in the upward direction.
White ball valves are solenoid valves, but I didn't have a good solenoid valve model.

All the pipes are the same in the model, but I'd use 1" for the main inlet/outlet and then switch to 3/4" where they split in two.

Under normal operation there should be no flow through the green pipes.
When the left tank is regenerating, the left two solenoid valves close. This blocks any water coming out of the tank (no hard water bypass) and also blocks raw water from entering the tank. Instead, treated water from the right tank provides water for regeneration/backwashing and for the house.

Now, if only I could find some cheap and reliable check and solenoid valves! Price is the only real downside I see, plus more (or just different) parts to break. It also definitely needs more space for plumbing, but it could be a lot more compact than what I modeled.

Any thoughts on this setup?

Oh, and I know there are a lot of potential issues with upflow regeneration (I'm not even sure I want it anymore), but let's save that debate for another thread if that's okay.

 

[ditttohead]

We do these regularly but only in very specific applications. Why do you want to do this and what is your raw water quality. Please don't think that this design is not already a normal design that will produce some unheard of water quality/efficiency etc.. this design is decades old but is only needed in very rare and unusual circumstances.

 

[Sponsor]

 

[Hatsuwr]

We do these regularly but only in very specific applications. Why do you want to do this and what is your raw water quality. Please don't think that this design is not already a normal design that will produce some unheard of water quality/efficiency etc.. this design is decades old but is only needed in very rare and unusual circumstances.

Hi dittohead, we were talking earlier about my setup (longer thread in the general plumbing forum.) This is one of the things I don't currently have in my plans, although it's not off the table. Just wanted to share the idea and get input.

If I were to do it, like you mentioned, it's not at all necessary. I enjoy doing things like this, and if I get slightly better water/efficiency out of it, that's good too!

With the already established implementations, is it the exact same thing? 2 checks and 4 solenoids? Does that setup have a particular name? How are the solenoids tied in with the control valves? I know it is possible, but I don't know the specifics of the relays on the controllers so I'm not sure how much in-between there would need to be.

A three-way valve on the input tee could take the place of two of the two-way valves for simplicity, but I haven't run across any that are specifically what would be needed.

 

[Reach4]

Hatsuwr would like the softener feature called "No Hard Water Bypass" for two softeners in parallel, that also uses upflow brining.

 

[Hatsuwr]

I was able to source the solenoid valves for $600 total... Might just have to do this.

 

[ditttohead]

Please call me before you waste a ton of money and time doing this. We do this but only in specific applications. You can get a car to get 70 MPG, but it is not going to be something you would want to drive... same goes for this. This is a fringe system that will get slightly higher efficiency but at what cost? $600 to save $2 in salt per year... seriously? Also consider the additional maintenance of the additional components, design time etc. This design really requires some very unique water conditions and applications to justify. What water conditions do you have that are so unique and complex that this design would make any sense?

 

[Hatsuwr]

Please call me before you waste a ton of money and time doing this. We do this but only in specific applications. You can get a car to get 70 MPG, but it is not going to be something you would want to drive... same goes for this. This is a fringe system that will get slightly higher efficiency but at what cost? $600 to save $2 in salt per year... seriously? Also consider the additional maintenance of the additional components, design time etc. This design really requires some very unique water conditions and applications to justify. What water conditions do you have that are so unique and complex that this design would make any sense?

Like I said, definitely not necessary for my water. Not doing it to try and save money - I'd probably change things up before it could ever pay for itself!
For me, it's more about seeing what can be done and testing new ideas. Plus, I enjoy the design, build, and test processed.

Now, if this is and old idea and well documented I'd be glad to not waste the money on nothing haha, but I haven't been able to find any info about similar systems. I don't exactly know what terms to search for though.

 

[Hatsuwr]

*edit 2*
Simplified the plumbing and reduced its size, removed a check valve, changed the solenoid valve models to actual solenoid valves, added some unions at the control valves and added two union ball valves to allow full isolation and ease disassembly.