Tunze Nano 3152 ATO won't shut off!

[08TRDOFFROAD]

I recently purchased a Tunze Nano Auto Top Off from Bulk Reef Supply.

I finally got around to installing it today and am having issues with it. The pump will not shut off, even with the switch submerged in water. I am getting pretty dang frustrated with this thing!

Any help would be appreciated!

 

[rvitko]

When a 3152 will not shut off the cause is usually a magnet and even possibly the magnet holder. Float switches are basically a magnetic ring in a float, flipping a magnetic switch in the post. If the glass is very thin, 3/16" or less, the magnet holder itself can pin down the float so it will not work, a shim of acrylic or rubber placed between the magnet and glass should solve it. Also make sure no other magnets are near the controller or float.

Another possibility is a siphon, the hose has to end higher than the water level in the reservoir or water will siphon to where those levels are equal, this would be the suspicion if you don't actually here or see the pump running.

 

[08TRDOFFROAD]

Wow! I feel dumb. It didn't even occur to me a magnet could interfer. I installed it on my wife's Biocube 29 in the return chamber on the back wall...right next to the magnet for the 9002. Moved it to the outer wall on the opposite side from the skimmer magnet. Works like a charm!

Thanks for the help and quick reply!

 

[Amatuer21]

I did the same thing and was very confused and thought it was broke. Your not alone lol

 

[nathenvan]

08TRDOFFROAD: if you don't mind I will post here also

I bought my nano ATO not long ago and am still having problems with either the pump not shutting off or pump too much water into the tank. I switched out with a smaller/weaker magnet that I got from ebay and it is still doing the same thing. re-position it and it would work for a week or so and acts up again. I need your help in resolving this issue, thanks

 

[08TRDOFFROAD]

No worries Nathen, hopefully we can get a solution to your issue as well!

 

[rvitko]

I would not use another brand of magnet, the magnets have a special shielding to protect the float as much as possible. On this glass I would use just a shim of acrylic or rubber between the outside magnet and the glass.

I would rule out a siphon if this continues after shimming the magnet and being sure the float is not near other magnets