Tunze Nano ATO - Working Opposite?

Colin Levy

Active Member
View Badges
Joined
Aug 29, 2017
Messages
130
Reaction score
41
What state or country do you live in
Kentucky
Rating - 0%
0   0   0
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?

1016172111.jpg
 
Last edited:
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.
 
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.
 
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...
 

IF YOU HAD TO TAKE A REEFING EXAM, WOULD YOU PASS?

  • Yes!

    Votes: 32 45.7%
  • Not yet, but I have one that I want to buy in mind!

    Votes: 9 12.9%
  • No.

    Votes: 26 37.1%
  • Other (please explain).

    Votes: 3 4.3%
Back
Top