Breaking a siphon

[georgeortiz]

Hey All!
Long time no post. To quote Alexwolf. "ahhhh Your alive!"
I have setup an auto top off system in my tank and periodically have a problem with a siphon effect beginning. This has caused a couple of close calls in my system but, what is the best way to create a siphon break?
Again just to clarify the situation.
I have a resevoir that is fed by my ro/di and controlled by my Kent auto top off float kit.
Once my float switch in my sump indicates more top off water is needed a pump in the freshwater resevoir is activated and water is pumped. A redundant float switch prevents overflows.
The problem occurs when the siphon allows more water into the sump than is necessary. This is out of the float switches control in the sump and if not caught in time can cause an overflow or worse turn my tank into a freshwater setup. Thanks in advance!

[::pete::]

If Im reading this right is it the remainder of water in the tube after its shut off?

If so lower the float valve so that when it shuts off then the remaining water will fill it to the desired level.

[Henry]

is the water coming out of the second float switch.

Okay, maybe I should ask this question first. Are they float valves or float switches that control an electronic valve or pump.

If you use a pump to fill your sump, you will need to lower your water tank/resevoir so water is can not flow freely thru the pump once it is shut off.

[brewercm]

Why didn't you just run the ro/di line and kent float valve directly to the sump and let it the float valve kick it off instead. That's what I'm doing to mine is straight to the sump to the level I want.

I don't trust electronic devices for cases like top offs, too many go bad and cause major problems. Here's a question for you.
How many times in the past year have you had even minor little power outages?
Now how many times in the past year has your toilet overflowed?

[GeoB]

Can you run the line from your topoff pump so that it empties into the overflow or into the main tank (above the water level of your topoff reservoir)? I run the line from my topoff pump into my overflow.

[brewercm]

Not sure how you have your line coming out of the reservoirso here's best I can think of. You can poke a hole into the line out where the water will spray out the side and still into the reservoir or the sump whichever would work better. Make sure the hole is above the water level, this will break the vacuum once the filling is done, may take little longer due to the loss out the hole but not much.

[Tim Marvin]

Put the return line up into your overflow or tank.

[Henry]

another vote for putting line into overflow

[georgeortiz]

Thanks guys for the input.

[Gator]

your reserviour needs to be hiogher than the auto top off, that way it gravity feeds to sump and the kent valve shuts off the water with no problems i have done it this way with a trashcan for 2-3 yeaars with no problems