Need new float switch for RO tank

[slash007]

Upper float switch on my RO tank went out and I didn't have a spare since it had never gone out. I was able to rig it and make it work with a vac flow switch to get buy, but need the correct one. I see 2 version on KR. This one is similar to what I had https://www.kleen-ritecorp.com/p-29278-poly-float-liquid-level-switch.aspx but they also have this one that says for RO. I am trying to figure out how it would work and which one is better https://www.kleen-ritecorp.com/p-17371-ro-storage-tank-float-switch.aspx . Thoughts? Thanks.

 

[MEP001]

The little poly float won't take any load at all, barely even a solenoid load. If it wires to a controller it'll work, and it's switchable to close on rise or open on rise by just flipping the float around, just pop off the retainer. I prefer the larger one on a wire, partly because I have two in the tank, one for low-water shutoff for the bay pump and I only have to keep one spare, and partly because the turn-on/turn-off range is a lot more so the system isn't turning on and off many times during the day. It can be wired for close on rise or open on rise.

 

[slash007]

I'm not seeing how the larger one installs and works? Does it just float on the water? I do have a 2nd float at the bottom of the tank for low water cut off, and it is the same as the poly one that was on top. I do like a bigger turn on/off range.

 

[MEP001]

You can zip-tie it to the top of the tank and add a weight of some kind near the float, although that's not even necessary. The main thing is to anchor the cord so the float dangles at your low point. It floats in the water and turns off a little past horizontal.

 

[slash007]

Sounds good, thanks for the explanation.

 

[slash007]

You can zip-tie it to the top of the tank and add a weight of some kind near the float, although that's not even necessary. The main thing is to anchor the cord so the float dangles at your low point. It floats in the water and turns off a little past horizontal.

I tried installing this today and it's not working like I expected. Turns on at vertical, but won't turn off unless the float valve is almost upside down. When I leave it in the water to float, it turns horizontal as the water fills up and slightly past horizontal, but not nearly enough to turn it off. Am I doing something wrong?

 

[Greg Pack]

I run my cable through a piece of PVC pipe to keep it from floating horizontally. You can drill a hole through the top of the tank and use about a 12" piece with a male adapter on it. You can then secure to the tank with a female adapter or a electric locknut. Then, run your float switch wiring through there.

 

[MEP001]

I don't like running it through PVC because it's a pain to change next time.

I tried installing this today and it's not working like I expected. Turns on at vertical, but won't turn off unless the float valve is almost upside down. When I leave it in the water to float, it turns horizontal as the water fills up and slightly past horizontal, but not nearly enough to turn it off. Am I doing something wrong?

You can put a weight on the cable near the float. The farther it is from the float, the more range it has between turn-on and turn-off. The weight will force the float to turn completely upside-down. Something like a 1/2" tee is plenty. I have a crapton of 1" x 1/4" bushings of which I carry around a few just to use as a weight on a float switch.

 

[slash007]

I don't like running it through PVC because it's a pain to change next time.

You can put a weight on the cable near the float. The farther it is from the float, the more range it has between turn-on and turn-off. The weight will force the float to turn completely upside-down. Something like a 1/2" tee is plenty. I have a crapton of 1" x 1/4" bushings of which I carry around a few just to use as a weight on a float switch.

A weight makes sense. I wasn't sure what you meant before. So are you using a 1"x1/4" bushing as a weight, or a 1/2" T? I can imagine sliding a bushing down the wire and placing it near the float (will it hold in place or do I need to do something else?) but can't imagine how you are using a T. Thanks.

 

[MEP001]

I usually forget to run the wire through the fitting and just zip-tie it to the wire 6" or so from the float. You'll still have to zip-tie the fitting in place, it just won't fall to the bottom of the tank if the zip-tie breaks if you run the wire through the fitting.

I've had to use all sorts of things for a weight, and have seen things I would never use including a 2" cast iron elbow and a doorknob.

 

[slash007]

I bought a 1/2" T and put it about 6" away from the float, but just spent 1.5 hours trying to get it to work. I think I finally figured it out, I had to leave the wire hanging inside about another 1.5-2' so that that weight had distance to drop and the float to rise. I got tired of testing it, so fingers crossed it's not flooded in the morning.

 

[MEP001]

Sounds like that should work. If I'd thought you would have so much trouble I would have drawn up a diagram.

 

[slash007]

Sounds like that should work. If I'd thought you would have so much trouble I would have drawn up a diagram.

Lol I would have requested one had I known how much time I was going to spend on it. You could still post one, there is a chance it still won't work. On another note, how low do you let it go with your setup before it fills again? I am looking at the camera my large tank is down by over 1/3rd and still has not been triggered to fill by the float. Weight is 6" away from float and then about 18" of cable from weight to hole in tank, which is on the side of the tank near the top.

 

[MEP001]

The length of the cable hanging in the tank will determine where it will come on. When there's an auto bay I try to set it to come on as high as possible, same if there's a reject recovery with a small capture tank.



In case it's not obvious, the square-ish thing is the weight, the round-ish thing is the float ball. Make sure the wire is attached to the tank so the maximum depth the float ball can reach stays where you want it.

 

[slash007]

Thanks. That's exactly how I had it setup, but for some reason it just didn't function as it should have. I'm thinking maybe I need more weight. I am using a 1/2" PVC T. I'll play with it more and get it dialed in. 1/3rd is too much, but maybe I moving the weight closer to the float will help too.

 

[I.B. Washincars]

You definitely need more weight than that. Use a stainless T. A brass T would work, but is susceptible to the water eating it up.

 

[MEP001]

I've always used a brass fitting. In my experience the RO water doesn't harm brass in the plumbing.

 

[slash007]

More weight makes sense. It's coming on at about half way empty and no way that keeps up on the very few days a year we are busy since it feeds 2 auto bays and the SS. It does seem like the perfect solution for my SS only wash though. There I find after some time that my TDS climbs up from around 15 to over 60+. I realized that for some reason the first little bit of water generated is of high TDS, so I have been disconnecting it every once in a while and letting it get down to about 1/3 of the tank, then connecting it back and when it makes a large volume, the TDS evens back out. This float would be great for there as it would not kick on until it had to generate a large amount of RO.