Tunze ATO malfunctioning - any help?

Hi all - in the last day or so my Tunze ATO has exhibited odd behavior - it appears incapable of keeping the pump on to top off the tank. When it turns the pump on - it keeps it on for about 2 seconds, then stops. Then it repeats for a while. On the controller it goes from 'low' to 'level' over and over.
Worse, it is not topping off the tank enough - my sump level is going down.

Power cycling does not help. Any clues? Anyone seen this behavior with your Tunze? I am surprised - it has always been flawless ... thanks in advance.

matt

 

I saw it once and it was because a snail had got up in the 'backup float' sensor and was lifting it while the laser was indicating it was too low.

If the float is not blocked, it may simply be too low in the water line. You want it a bit higher than the actual water line. "It" in that sentence is the point where it beeps at you when raised.

Also make sure the laser is clean - you do have to wipe coralline and stuff off it from time to time or it gets a little weird.


I remember you talking about replacing the pump recently, did you do anything with that?


Last thing I can think of is make sure you're *not* bubbling/breaking the surface with a PH right where the sensors are. Can confuse it I've noticed on the laser side.

 

Tried all of the above per your suggestions to no avail .
Float works fine - tested.
Laser not that dirty - cleaned it anyway.
Located in sump in a low turbulence area...
Weirdness.
I do have a spare one of these from my old tank in the garage and the manual - I will at least look at the manual and see if there is anything there. Notified Roger from Tunze too...
Thanks for the suggestions though Peredhil!

matt

EDIT - I have not replaced the pump - perhaps it needs to be now...

 

From Roger - sounds like the pump after all:

 

warranty? my exp w/the tunze folks has been excellent.

 

I am hitting him up on warranty as I appear to have a bunk unit. Check out what I just told him...

Ok - I am lucky to have an old one in the garage. At first I just swapped out the pump - same behavior!

Then I swapped out the whole unit with the old one (old 5017 controller and older, bigger power supply with selectable voltage - on 9v setting) and I am back in business.

So on my newer model with the slim 11w 1600mA power supply - I have problems as described above. It does not appear to be pump related.

matt

 

It's neat you had an older unit to kind of prove your point.

I didn't realize those older ones had selectable voltage, is that so you can use different pumps?

My bet would be they take care of you... We'll see.

 

You bet right! Tunze wants the whole unit back and will replace it. 8)

As for the power supply - I am not sure. Roger did indicate the new pumps have a double seal and require more power - the old ones ran 9v (although they do look the same to me and they have the same model number)..

I will say this.. the new one that requires more power is the one I was whining about a while back as far as noise went. So I think this more power required thing has jacked up the decibel level. Putting my old one back one - the first thing I noticed was how quite it is. I think I will leave this one on.

matt

 

Sometimes newer isnt always better.