Automatic Top Off ... how?

[platapus]

Im looking for an automatic top off solution? Using a RO/DI unit installed under the tank, what are my options? I have hear the if I using a float valve for this, has problems shutting off becuase the water level rises too slow? Is this true?

[rottn]

Hi platapus - we use a Kent's float valve for our topoff system. It works perfectly fine.

When water is needed for topoff, the valve opens immediately (reaction time is instantaneous), and it will ususally run for about 5 minutes to bring water levels back up.

The only way to make it work any quicker, would be to use a reservoir. That way, you would have the water already made for the demand, vs. the water being made at time of demand.

We just have ours go directly from the RO/DI unit into the sump though, and it works fine.

HTH

[Doug1]

Question regarding having the RO feed a float valve directly. What happens to the RO while the float valve is closed, does all the water go out the waste line? I fill a trash can to feed mine

[platapus]

The solution I would like to implment, would be to run PVC plumbing to the back of my cabinet, hook up to the RO/DI, controling the water ON/OFF using a float valve hooked up to and automatic spinkler valve.

[chewie]

Doug,

"What happens to the RO while the float valve is closed, does all the water go out the waste line?"

The way mine works is I have an Automatic Shut Off on my RODI.

As soon as the float valve closes, pressure builds and the ASO shuts down the incoming water to the unit.

I don't have my topoff run off of my RODI unit because it would cause my unit to run every 30 min for about 5 minutes.

Instead, I use a old salt bucket as my resevoir, and I have to refill it every 3 days. The bottom of the bucket is about an inch higher than the water level in my sump. In the sump is my float valve.

Gravity is our friend

Jon

[rottn]

Hi Doug,

Yes, our's has an automatic shut off too. As soon as the float valve closes, the water supply shuts off.

I don't have my topoff run off of my RODI unit because it would cause my unit to run every 30 min for about 5 minutes.

Hi Jon - how come your unit would run that often? Are you evaporating THAT much?

When the valve drops (due to water levels), the water will top off. When it rises back to level, the water will stop. So, you are getting what you need, no?

Just trying to understand your setup (and see if maybe I am doing something wrong). Just seems (to me) like it's defeating the purpose to have to fill up a reservoir every 3 days.

Thanks!

[kita_katan]

I have about a 30 gallon reservoir hooked up in my closet that runs to the sump and hooked up with a float valve...I usually have to fill it once every week to week and a half.

[chewie]

Rottn,

You are correct! I evaporate about 2 gallons a day on my 135g.

I originally hooked my RO/DI to the float but I didn't like the idea of the RO unit making water in short spurts.

I have no proof but my thinking led me to belive that it is better to make 2 gallons all at once instead of over a 24 hr. period.

Plus, all my topoff water is limewater, that would be hard to do without a resevoir to mix/settle the lime in.

Jon

[Zephrant]

There are posts around from manufactures of RO/DI units that indicate that the first water produced after the RO has been shut off is pretty nasty. Although the DI should absorb most of it, if you are continuously starting and stopping the RO unit, you are most likely dumping in much more junk then if you run it once a day.

Zeph

[rottn]

Hi Chewie - ah yes - limewater! That, of course, makes perfect sense. Thanks!

I guess having a reservoir or running straight from the RO/DI unit is a personal preference thing though otherwise?

We just like the idea that when we are ready to go for vacation, the only thing we would REALLY have to depend on somebody for is feeding the tank. And even then, the food would be proportioned, packaged, and labelled with dates to be fed!

(I'm not paranoid, am I?)

[shalori]

i don't think you're paranoid, rottn, since i've been thinking the same thing! i've left twice since i've had the tank up, and both times, despite what i thought were error-proof instructions, i've come home to a mess. so i'm, now, trying to figure out how this whole top-off system works, myself. i just haven't had the time, lately, to do a search. in fact, i need to be taking off, now, gotta math test this morning. ugh.

[schulz1616]

I have a self-sustaining 35g except for when I have to add water to it. Could I get a top off system for my tank even though I don't have: a ported tank, sump, etc.? Or is there some other route that I can take?

Jesse