View Full Version : Tunze 3152 Automatic Top off Nano Osmolator not working

03/05/2017, 11:19 AM
I purchased a Tunze USA 3152.000 Automatic Top off Nano Osmolator for Aquariums Under 55-Gallon back in November 2016 and now it doesn't work anymore.

If I unplug it and plug it back in then it pumps water into the sump. It then stops after about 2minutes which seems normal since water level is below sensor. However, when I fill it up completely and the sensor stops the unit, it never pumps any more water after water has evaporated. Basically the unit is rendered useless. I have to then unplug it and plug it back it back in and it pumps again until either it stops on it's own or the sensor stops it. However again next refills on it's own.

When the water level is below the sensor i hear in pump kick in every 30seconds but it stops immediately and nothing happens.



03/06/2017, 09:48 AM
This sounds like the normal Safety Timer, out of the box the unit is set so the pump times out after a 1 min 48 second run, it then shuts down and will pulse the pump as an alarm to let you know it timed out. It will never run again until the power is cycled. The float has to rise within the time limit to reset the timer. For tanks over 25 and under 55 you need the 3 minute timer setting. The safety timer is explained on pages 21-29 of the manual and is a safety in case the float were to ever stick or fail.