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Why doesnt this work with R.O. filters?


phiber_optikx

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phiber_optikx

Somebody school me.... I have my rodi filter set up directly to my float switch. Why can't you do this on an RODI unit? Have only made +/- 250 gallons including tank fillup and the filters are 1/2 spent already..... So why doesn't this work?

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why doesnt what work??? i dont understand? the float swith on your rodi? if so, then it could be the water pressure from your house is too strong for the float switch.

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jedimasterben
Somebody school me.... I have my rodi filter set up directly to my float switch. Why can't you do this on an RODI unit? Have only made +/- 250 gallons including tank fillup and the filters are 1/2 spent already..... So why doesn't this work?

How do you know the filters are "1/2 spent"? What system do you have?

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Somebody school me.... I have my rodi filter set up directly to my float switch. Why can't you do this on an RODI unit? Have only made +/- 250 gallons including tank fillup and the filters are 1/2 spent already..... So why doesn't this work?

 

How did you determine that it is half used already after 250 gallons?

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phiber_optikx

"How did you determine that it is half used already after 250 gallons?"

Because the micron filter is already dark brown after 3 weeks of use and my color changing D.I. resin is beginning to change as well.

Can I know for sure exactly how much longer these filters will last? No, but in my experience my filters should look nowhere near that spent after less than 1 month of use. Also, no leaks, it is not constantly adding water, I assure you it turns off when the float tells it to. It is a 6 stage uinit 150gpd. All filters are installed correctly, this is not my first R.O.(deo)

 

I have a friend who works at a fish store and they use the same unit I do. They said when they had it set up on floats it was doing the same thing as mine..... So is it the fact that it trickles a small amount of water every 30 seconds or so? Does the float keep it from building enough back pressure to function correctly? Any ideas?

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phiber_optikx

Not sure. I will have to dbl check when I get home from work. Usualy around here it is 250-400 tds. It is water general brand if I remember correctly.

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TDS creep is burning up your DI. I always flush my RO line with a 'Y' valve before making DI water.

My RO is like 6 tds after it runs, but it's like 100 + when it first turns on after a while.

So with the float turning it on an off the water your DI is receiving is likely very high tds.

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TDS creep is burning up your DI.

So with the float turning it on an off the water your DI is receiving is likely very high tds.

 

That could be the DI issue solved. TDS creep from the RO membrane. As for the micron sediment stage issue, that is before anything else and therefore is only impacted by the source water. If it is nasty so soon....that just means your source is nasty. Maybe you just happen to have a lot of a certain element in your water that is very apparent when it builds up (looks brown). The sediment filters are cheap....buy a 20 pack on Ebay and replace every few months.

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also dont use too fine of a sediment filter in the first stage. start with with a 5-10. if you use too fine of a filter on the first stage it will plug up fast and the other two wont do a thing.

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phiber_optikx
TDS creep is burning up your DI. I always flush my RO line with a 'Y' valve before making DI water.

My RO is like 6 tds after it runs, but it's like 100 + when it first turns on after a while.

So with the float turning it on an off the water your DI is receiving is likely very high tds.

So is there no way to have an ro set up directly to a float switch?

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phiber_optikx

I guess my best solution is simply to turn off the float and turn it back on whenever the water gets really low..... This will still add a small amt. of creep but only once or twice a week as opposed to every 45 seconds or so.... Any better suggestions?

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RO membranes work best with nice long filter runs, frequent starts and stops kill them as they never get properly flushed. In turn this eats DI resin like crazy.

You best option is a solenoid valve with float switches in place of a float valve. Set the float switches a good distance apart so the filter runs less frequently and for longer periods of time so it stays well flushed.

I always discourage float valves, especially if they are in a sump and not a ATO storage vessel. I have my float switches set so the RO must make 11 gallons per cycle and the resin lasts over 1000 gallons with a tap water TDS of 630. The RO only stays between 2 and 3 and the DI is of course 0 TDS.

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RO membranes work best with nice long filter runs, frequent starts and stops kill them as they never get properly flushed. In turn this eats DI resin like crazy.

You best option is a solenoid valve with float switches in place of a float valve. Set the float switches a good distance apart so the filter runs less frequently and for longer periods of time so it stays well flushed.

I always discourage float valves, especially if they are in a sump and not a ATO storage vessel. I have my float switches set so the RO must make 11 gallons per cycle and the resin lasts over 1000 gallons with a tap water TDS of 630. The RO only stays between 2 and 3 and the DI is of course 0 TDS.

I would not have the RO/Di feed the sump directly. Have it fill a storage vessel. Have the Storage vessel feed the tank. Don't need to run the RO/DI all the time, just when the storage vessel starts to get low. Plus you can heat the water to the same as the tank.

 

Also do you have a shut off/float valve similar to this?

http://www.marinedepot.com/SpectraPure_Aut...IRORASO-vi.html

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phiber_optikx

Yes, most newer systems have them placed inline. Can somebody explain to me how the solenoids work? Do you place it on your 1/4" tubing and it opens when the sensor tells it the tank is low? Can you set them up on a two float (min-max) system?

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As previously mentioned, RODI units do not work efficiently with constant starts & stops. Better to feed a reserve... Pump a gallon (or several) at a time then use that to provide for your ATO. Do not directly feed your tank. Besides the fact that it will decrease the life of your membrane, if your float ever fails then you could be in for a messy treat when your tank overflows. Your membrane should last a long time assuming you don't have nasty water and your carbon filters effectively remove the chlorine.

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phiber_optikx

"Pump a gallon (or several) at a time then use that to provide for your ATO"

This is for a 125 with a 75 gallon sump. So I will be topping off more than "a gallon" if I set it up with two switches.

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"Pump a gallon (or several) at a time then use that to provide for your ATO"

This is for a 125 with a 75 gallon sump. So I will be topping off more than "a gallon" if I set it up with two switches.

 

Then I don't see the problem. Usually I pump 2 gallons at a time on my little system that can produce about 24 gallons per day Not sure how big yours is but I assumed we were talking about a nano tank.

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phiber_optikx

Problem WAS tds burn on resin. So my solution at the moment is turn off the unit for a few days until water gets low and then run it so it is using more water. However, this isn't really an AUTOMATIC topoff if I am pushing buttons a few times a week. So, how does a solenoid work? Is there a way I can have something mechanically close the 1/4" R.O. line and automatically open up when a sensor tells it to?

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