weatherson
Premium Member
Maybe I should try and think of a shorter name.
I posted some information and images to a project I have been working on at my thread but thought I would duplicate it here. It's better suited here anyways considering all the creative minds that frequent this forum. So here is the text and photos for your review and possible enjoyment;
So I've been mentioning that I've been working on updating my auto top off (ATO) system. What I was trying to achieve or improve upon was to reduce the amount of times the RO/DI filter was cycling on and off. Currently, my system includes a small reservoir which is feed by the RO unit with a float valve to regulate the water level. This then feeds my Kalk-Reactor via gravity and then continues to another float valve located in my sump. This valve maintains a constant level for the tank and provides the Kalkwasser (calcium water) additions for the coral growth. The problem with this system is that the float valve in the reservoir is constantly cycling the Ro unit because it turns on with only a small decrease in water level; the evaporative tank water replenishment throughout the day. This wouldn't be an issue if it weren't for the fact that RO units apparently pass small amounts of impurities every time they start production. So, the more times it cycles, the more impurities get passed through and to the tank. This is not ideal or a good thing. The best or one way to decrease this amount of impurities is to have the RO cycle less by producing a large amount of water at a single time.
I didn't want to give up on my overall ATO design due to the fact that it's worked flawlessly for many years, at least I thought prior to recently learning of the impurities issue. I knew I could increase the reservoir size which would help slightly but not to the level I needed. What I really needed was for the reservoir to empty almost to the very bottom before the RO unit would start and fill it to the top again. And, I needed to do this with a single, mechanical float valve. Hmmm. Better turn the left brain up a notch for this one.
What I came up with is a fairly simple design that does in fact utilize only one float valve. Although I will be adding a second as a backup, safety device. A good way to see the design in action is to fill your sink with water and then submerge a drinking glass in it. Now, turn the glass up side down, still under the water, and slowly raise it out of the water. Note how the water remains in the glass until its opening reaches teh air/water surface. Then air enters the glass allowing the water to escape. Just before this point, the water within the glass is under a vacuum due to gravity (water is heavier than air). That's pretty much the basis for my design. Simple. Sort of. The idea is to create a separate chamber that the float is mounted inside of. This chamber has an open bottom that sits just above the reservoir bottom and the output of the reservoir. The need now is to keep the float valve in an off or up state until the water level inside the reservoir dropped to the bottom of the float chamber. Not a problem as long as the air in the chamber is allowed to escape as the water level rises during the filling stage. But then the chamber must not allow air in as the water level drops, just like the glass in the sink. The simple solution to this was to attach a check valve to the top of the chamber. This allowed air to escape but not renter. Perfect.
Now that I had the issues resolved in my mind, it was tme to build a prototype and see if it would work in reality. So here is my first design attempt;

So I've been mentioning that I've been working on updating my auto top off (ATO) system. What I was trying to achieve or improve upon was to reduce the amount of times the RO/DI filter was cycling on and off. Currently, my system includes a small reservoir which is feed by the RO unit with a float valve to regulate the water level. This then feeds my Kalk-Reactor via gravity and then continues to another float valve located in my sump. This valve maintains a constant level for the tank and provides the Kalkwasser (calcium water) additions for the coral growth. The problem with this system is that the float valve in the reservoir is constantly cycling the Ro unit because it turns on with only a small decrease in water level; the evaporative tank water replenishment throughout the day. This wouldn't be an issue if it weren't for the fact that RO units apparently pass small amounts of impurities every time they start production. So, the more times it cycles, the more impurities get passed through and to the tank. This is not ideal or a good thing. The best or one way to decrease this amount of impurities is to have the RO cycle less by producing a large amount of water at a single time.
I didn't want to give up on my overall ATO design due to the fact that it's worked flawlessly for many years, at least I thought prior to recently learning of the impurities issue. I knew I could increase the reservoir size which would help slightly but not to the level I needed. What I really needed was for the reservoir to empty almost to the very bottom before the RO unit would start and fill it to the top again. And, I needed to do this with a single, mechanical float valve. Hmmm. Better turn the left brain up a notch for this one.

What I came up with is a fairly simple design that does in fact utilize only one float valve. Although I will be adding a second as a backup, safety device. A good way to see the design in action is to fill your sink with water and then submerge a drinking glass in it. Now, turn the glass up side down, still under the water, and slowly raise it out of the water. Note how the water remains in the glass until its opening reaches teh air/water surface. Then air enters the glass allowing the water to escape. Just before this point, the water within the glass is under a vacuum due to gravity (water is heavier than air). That's pretty much the basis for my design. Simple. Sort of. The idea is to create a separate chamber that the float is mounted inside of. This chamber has an open bottom that sits just above the reservoir bottom and the output of the reservoir. The need now is to keep the float valve in an off or up state until the water level inside the reservoir dropped to the bottom of the float chamber. Not a problem as long as the air in the chamber is allowed to escape as the water level rises during the filling stage. But then the chamber must not allow air in as the water level drops, just like the glass in the sink. The simple solution to this was to attach a check valve to the top of the chamber. This allowed air to escape but not renter. Perfect.


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