Help. Issues with Nano Osmolator

CayoHueso · May 3, 2024

I've had my Tunze Nano ATO setup since December and never had any issues. Besides air sometimes getting trapped in the pump, but it's pretty easy to shake out. Last week I noticed that the water was extremely low in the rear chamber of my AIO. There was plenty of water in the ATO reservoir (5 gal bucket). I cycled the power to the ATO off and on and the pump came on and filled the rear chamber until the water reached the float sensor and switched off like normal. The water in my tank evaporates pretty quickly because we use dehumidifiers in the house. I came back a few hours later and no issues, the water level was still at the sensor. Over the next few days everything continued to work fine, I even witnessed the ATO work top off the tank.

Fast forward to today and again the water level is super low. I cycled the power off and on and the pump kicked in again. This time I had to cycle it twice because the safety feature kicked in and stopped the pump before the water level could reach the sensor. Once it reached the float sensor the ATO turned off as it should.

I'm not really sure what the issue is. I haven't changed anything about the setup, so I can exclude certain issues like; magnet interference, placement/orientation of the float switch. The float seems to move freely and the sensor seems to be operational because as I said I witnessed it top off the tank, and after I cycle the power the sensor calls for and activates the pump and deactivates it when the water level is at the correct height. It's also not just the pump priming, because if I cycle the power and the water level is at the sensor, the pump doesn't activate and doesn't pump unnecessary water. The pump is functional and not air trapped because it's pumping water. However, over time I have noticed the stream from the pump is considerably weaker. I don't add any supplements or dosing to the ATO water. The only thing I can figure is maybe an issue with the controller?

Seems like there are lots of posts with similar issues, but either no solution/fix is posted, or I can rule out the issues I mentioned above. Any trouble shooting help is much appreciated.

rvitko · May 4, 2024

I made a video on the Nano Osmolator with most everything you can check, it is almost never the controller. The most common issue is not understanding the safety timer, if the pump is twitching every 10 seconds, the issue is the safety timer and it is just timing out. I am headed to Germany, I will check back in as soon as I get there and get settled. My focus would be on the pump, it is a much more sophisticated system than most people think, if that pump uses excessive power, it may well work but the power will be cut off, this is only reset by cycling the power. Shaking the pump is not very reliable, the pump should be tipped upside down while submerged to fully purge the air, shaking often moves the bubble to one side, the pump works for that cycle, the bubble moves back, it doesn't work on the next cycle, this can be a cause of time outs but the time out is always indicated by a twitching pump, a pump that stops cold will usually be a dying pump. The bobber may move freely, but this does not totally rule out magnet issues, I discuss this in the video.

CayoHueso · May 10, 2024

rvitko said:
I made a video on the Nano Osmolator with most everything you can check, it is almost never the controller. The most common issue is not understanding the safety timer, if the pump is twitching every 10 seconds, the issue is the safety timer and it is just timing out. I am headed to Germany, I will check back in as soon as I get there and get settled. My focus would be on the pump, it is a much more sophisticated system than most people think, if that pump uses excessive power, it may well work but the power will be cut off, this is only reset by cycling the power. Shaking the pump is not very reliable, the pump should be tipped upside down while submerged to fully purge the air, shaking often moves the bubble to one side, the pump works for that cycle, the bubble moves back, it doesn't work on the next cycle, this can be a cause of time outs but the time out is always indicated by a twitching pump, a pump that stops cold will usually be a dying pump. The bobber may move freely, but this does not totally rule out magnet issues, I discuss this in the video.

I can't seem to figure out the issue. It ran fine from last week all the way to today. I'm familiar with the twitching, and the pump isn't twitching. It's just silent, and not running. Once I cycle the power, it kicks right back on like normal and seems to operate that way for a few days before malfunctioning again. The stream from the pump is considerable weaker that it used to be. The two issues seemed to show up at the same time, so maybe it's an issue with the pump. It does run a lot. I go through a 5 gallon bucket of RO/DI water in about a week. I did pull the float sensor and cleaned it. There wasn't anything inside the float cover blocking the pump. But there was some growth on the outside of the plastic shield/cover that I cleaned off.

rvitko · May 10, 2024

I would say almost for sure this is a bad pump, if the pump uses more than 900mA, the controller shuts off power to the pump completely and this is only reset by cycling the power. If I can get a copy of the receipt and serial number we can get out a replacement pump, I won't likely be back online until Tuesday, I am in Germany and today Interzoo ends, we will tear down and return to the factory and after that I begin the trip home.

rvitko · May 10, 2024

I would say almost for sure this is a bad pump, if the pump uses more than 900mA, the controller shuts off power to the pump completely and this is only reset by cycling the power. If I can get a copy of the receipt and serial number we can get out a replacement pump, I won't likely be back online until Tuesday, I am in Germany and today Interzoo ends, we will tear down and return to the factory and after that I begin the trip home.