Tunze Nano ATO - Working Opposite?

[Colin Levy]

Bought a Tunze Nano ATO (3152) used. It came in good shape, all put together.

Installed it into my new IM25 Lagoon, back middle chamber as I have seen everyone do.

I overfilled my tank, so the whole unit was underwater. I plugged everything in and the ATO kicked on and started pumping water on. I quickly took off the magnet, pulled it out of the water, the float switch dropped and the pump stopped.

Now I am new to ATOs, but that seems opposite. When the float switch drops (no water), the pump should then kick on. Mine is working backwards.

I have attached a photo. As you can see, the unit is out of the water, or just barely, but the float switch is all the way at the bottom, but the pump won't kick on. I just dropped it down in the water and the pump kicked on...

I tried searching around and no luck. The tank's glass is pretty thick, so it's not a magnet problem. The float switch is defiantly moving freely.

I am so lost. Am I doing something wrong? Could it be wired backwards?

 

[Grey Guy]

Find a manual for it and make sure it is put together and installed correctly. The regular size Tunze ATO is easy to put together wrong and get it working backwards.

 

[SashimiTurtle]

+1, make sure the float isn't upside down.

 

[alyee5]

Here's the manual.

https://www.tunze.com/fileadmin/gebrauchsanleitungen/x3152.8888.pdf

 

[Wankell]

You need to flip the float cylinder upside down. Im almost certain someone replaced the float with a non nano version, the nano float operates in reverse.

 

[Colin Levy]

You need to flip the float cylinder upside down. Im almost certain someone replaced the float with a non nano version, the nano float operates in reverse.

That was 100% the problem. It works like a charm now. Thank you very much! I would never of been able to figure it out.

Wonder if that is why the guy sold it to me at a heck of a price after having it for only 2 weeks...