Auto Top Off styles??
 

I have seen many versions of ATOs and they all seem to work just fine, I just don't get why people go to this expense for a complicated solution. I simply use float valves off my RO/DI and I wonder why more people don't go this route. You can't add Kalk this way but there are other ways. The idea of constantly refilling a container put me off the ATO path early on.

To elaborate on what I do, it's really pretty simple. I run a float valve in my sump and one in my mixing barrel that are fed directly from my RO/DI. When either my tank or mixing barrel evaporate off enough water, the float valve falls and allows it to refill to the set level. To avoid excessive cycling of my RO/DI, I have it run off an outlet on my controller set to be on for 15 minutes, 4 times a day. This timer is also a bit of a safety factor if something goes wrong. I don't touch a bucket, a tap, or anything to top off either.

I can't think of a simpler way and wonder why so many people with RO/DI setups still use an ATO. Am I missing something? I'm a bit of an automation junkie but this isn't too complicated. I'm interested to see what the consensus is.

Float valves screw up that's one big reason not to have it set up directly to an endless supply of water. I like my solenoid system dual nc valves and the boost pump hooked up to a wall type count down timer. Total shutdown every time with a very slim chance of failure. Not to mention I have a timer set for the same time that the system is running and I religiously check to make sure that the system is secure before I go to bed its to the point that I can't sleep enless I've checked. Even calling when I'm staying somewhere else for the night.

I would say ATO sensors screw up just as often as float valves. When is the last time your toilet tank violently overflowed? Even at city pressure 24/7.

The timer is the safety factor that keeps it from being a constant supply of pressurized water, and the timer is tuneable to meet your specific ATO needs, down to the minute if you wish.

I don't think twice about mine, even on 3 week vacations. A 100 GPD RO/DI can only make about 250ml of water per minute. If someone hasn't noticed that a sump or barrel is slowly filling over several days, eventually you will experience a spill of a few litres at most. Not really a big deal or risk IMO.

Is this using RO/DI? If so, what fills your storage container?

i have ro/di lines ran throughout the house so i don't need to bring out any hoses to do a top off i just open the valve to the tank i want to fill (lines are secured to the sump) and hit the timer to activate the timer on the ro system than i set a backup timer on my phone that is always on me so no matter where i am i get a reminder. each tank ive got the times down to a science as i always top off at the same mark. when i fill a mix tank up again i know how long it takes to fill and the timer even at its longest time setting wont flood it also the mix tanks are in the unfinished utility room that's equipped with a floor drain. we installed this system after flooding 1/3rds of the house :redface:. i typically dont have a storage container of strait ro/di. your system sounds rather similar to my setup just a top off has be manually started but will automatically stop after the desired amount has been dispensed.

My RO/Di is a floor away from my sump :-(

Where did you get your solenoids?

I'm having difficulty finding solenoids that are entirely plastic, no metal...

+1

autotopoff.com?

Have you tried looking on ebay? That is where I found mine.

The manufacturer of my RO/DI recommends that it run for several hours at a time. Short run times are apparently damaging or at least reduce the lifespan (or maybe effectiveness? I don't remember why exactly) of the membrane.

I've had problems with sensors, valves and solenoids sticking either on or off in the 9 years that I've been doing this. By storing a few days worth of purified water in a separate container and pumping it to my main tank I minimize the risk of over diluting my tank. I've known a few people who have overflown their tanks or flooded their homes with either poor design or neglect.

My RO/DI unit is 30' from my tank and I was able to run a water line to it so I'm not sure about what the rest of you are talking about.