ATO failure
 

My ATO system (JBJ) failed last night the float in the sump quit working correctly it was telling my ATO that the water level dropped and telling it to turn on the pump even though the water level was fine so I had 20 gallons of water added to my tank but was not aware of it until this morning when I stepped in wet carpet. Fortunately only about 8 gallons went into the tank while the rest went on the floor salt went from 1.026 to 1.025 so not a huge change.




I dodged a huge bullet but paid for it in wet rug it was a win/lose for me

sorry to hear this. its why I only use a gravity system

Oh man, that sucks. Hearing this more and more. Sounds like you got off lucky. Good example of the need for backups of backups and failsafes.

where your float sensors are......is there decent water movement? is it in the same compartment as your dosing?

I had my gravity feed system fail as well. The only real answer is to limit the fresh water in your reservoir to 2 to 3 days worth of water max. And have a large enough sump to be able to handle that water if the top off system should fail.

I have a basic sump system skimmer and return pump in a two tank sump system (skimmer in one tank and return pump in the other) ATO float is in the return pump tank

I hate wet floors!
Although I mostly trust my Tunze 3155, I have it plugged into my controller and a float switch in the return section. This will only allow 2 gallons to flow IF the ATO controller sticks 'on'.
The ATO has access to a max of 9g, which in my 115g system would drop my DT from 1.026 to only 1.024. And my sump could handle it all; unless the return pump were to then stop!!

Redundancy and fool proof failsafes are the only way to avoid disaster.

The limiting the amount of water in the reservoir is the safest.

Electronic ato can always fail. Nature of the beast.

Gravity fed can also fail... Something gets stuck on the float, etc.

I've had issues with both methods.

I've only had a near hobby ending experience with my gravity fed. (Mind you it was with a large reservoir going through a kalk reactor)

Just curious are you using a higher output pump with your jbj or did the internal timer in the ato unit fail? The jbj ato has an adjustable timer in it that you can set so it will ony allow the pump to run for so long regardless of what the float switch says

The JBJ was second hand when I got it but was in very good condition however the timer function stopped working a couple of months after I got it and until yesterday the floats worked flawlessly (second set of floats for it as the first set failed 2 years ago) I have a a powerful but small pump

Sadly I will have to wait til the new year to buy another ATO system I’ll just have to plug and unplug the ATO as needed no big deal atm

Just buy a simple timer plug. Set that to be on for a short period multiple times throughout the day. The combination of timer and float should prevent floods.

I have mine set to run for 5 minutes every couple of hours. I figured this out just by noticing usage across a couple of days. That way if level sensor fails, it can't run for more than timer. And by the time the timer kicks on again, enough should have evaporated to handle next cycle.

Variation of gravity feed ATO that has worked well for me many years without failure. Couple close calls, one when tank being babysat by my folks. Other than that, simple enough to minimize the impact of failure.

http://www.canreef.com/vbulletin/sho...6&postcount=11

I think Tunze with 2 sensors as back up is a great investment!

I used to use a Tunze, but after about 10 years it started acting up so I appointed my Apex controller to do the job because I already had enough spare parts laying around. I use two simple float switches from eBay into the breakout box and a little Hydor utility pump. I used to use Maxi Jets but they would only last for about a year before the impeller blades would fall apart. This is my program:
Fallback OFF
Set ON
Min Time 000:30 Then ON (so that the pump runs for at least 30 seconds whenever it comes on)
If Sw5 OPEN Then OFF (one float switch)
If Sw6 OPEN Then OFF (second float switch for redundancy)
If Sw4 CLOSED Then OFF (water on the floor sensor)

My freshwater reservoir holds a maximum of 13gal which is not enough to overflow my sump and replenishes itself ever 1-2 days with RO/DI water which is controlled by a solenoid on a timer. I evaporate 3-4 gal daily. I've had some issues with these ATO systems not coming on and my sump water level dropping a bit before I noticed but never staying on and causing a flood.

sorry to hear about the failure. The JBJ has a failsafe timer that should have prevented that. I run mine with a weak pump so if the float sticks the change in sg is minimal before the timer shuts it down. It has been working great for 8 or 9 years so far. But I suppose if the relays or logic circuits fail the failsafe might not help, fingers crossed I don't find out.

Mine did the same thing minus the flooding, my sump was full to the top though. I'm not sure whether it was a sensor or the ATO unit failed, I went back to gravity fed and it works just fine.