I go through pumps like candy

[ataller]

Due to my schedule I will often be away from my tank for a couple days at a time. During which, it seems every couple months, my ATO reservoir will run dry.

One of the reasons I bought the osmolator is because I was under the impression that the pump/controller can tell when the pump is running dry and shut it off.

Is this true?

If it is, it seems that maybe my controller isn't working? Because if the reservoir runs dry, my pump end up running, overheating, and the plastic I guess melts and the pump is finished. Then I have to replace the pump.


Any thoughts? Ideas to help me save from having to replace the pump so often.


Adam

 

[rvitko]

The osmolator has no system to detect if the pump is running dry, but the pump is not water cooled or lubricated and is not harmed by running dry for the brief time the controller allows the pump to run, after 10 minutes of running without a fill being registered the controller shuts off the pump. The pump is a simple low voltage DC hobby motor inside a waterproof housing with a direct drive shaft through a dual oring seal. Do you actually see signs the pump has melted and overheated? Are you sure the pump doesn't work and that it isn't an issue with the controller? The controller has a current limiter for the pump, if the pump draws too much power for the current limiter it cuts off power to the pump. If the wiring or connector is corroded or shorted or the current limiting switch is defective, these could all make it appear as if the pump is the problem, but it is not, the controller has cut power to the pump so it has enough power to run its basic safety functions. The older pumps had single seals (2+ years ago) these typically lasted 12-24 months. The new pumps use a dual seal and they last twice as long on average. The only thing that I have seen kill these pumps prematurely is kalk slurry, bits of plastic or gravel in the reservoir, or occasionally, a defect. If this osmolator is a couple years old, it likely has the 800mA current limiter, the dual seal pump will use 1000mA at 12V but will be under 800mA if the wiring is good and you use a 9V power supply. New osmolators use a 1200mA limiter and this is safe because the power supply on new osmolators can deliver 1600mA while old ones used an 800mA or 1000mA power supply, which will be fine so long as you stick to 9V, clean wire and 4-7 ft of head pressure (lower head pressure increases current draw). In short, if this osmolator is a couple years old, either stick to 9V and check your wiring and head pressure or, it needs to be sent in and have the current limiter upped and you need the new power supply.

 

[ataller]

Ok that was very detailed had to read it a couple times to wrap my head around it. Thank you.

The last 2 pumps that went the metal shaft that spins that propellor came lose of the plastic propellor so the metal shaft would spin and the propellor obviously wouldn't. So I assumed it was a heat problem. Both times I replaced these pumps, a new pump worked flawlessly.

The pump that went before this would still push a small amount of water, but only against zero head pressure, I had to bring the reservoir up to the level of the tank. I am of the opinion that that pump died of old age, so no problem there. All the problems started when I replaced the original pump.

This time it is different. When the controller switches to fill, the pump does nothing. When I attempted to spin the impellar by hand it was jammed and wouldn't spin. Again I assume something inside melted and the plastic impellor fused together with something. I have ordered a new pump, which should arrive next week, I won't know until then if it is a pump issue or a controller issue.

I do have an older osmolator control unit, probably around 2-3 years old. I have checked the wiring and there have been no changes to it since the pump was working. The yellow light will turn on as if the controller is supplying power to the pump, and if I manual top off the tank the controller will switch to green. When I found the pump, that had run dry over the weekend the controller was showing a red light (indicating the pump was running dry).


I do not run kalk through my pump, and use only RODI water, I doubt that there are any bits and pieces of gravel or some such in the reservoir as only RODI water goes into it.

Head pressure is probably 2-3 feet only. I just checked the power supply with my unit and it is 800mA.

I did notice that it was set to 12v instead of 9v. It has always been set to 12v I have never played with it. Will this cause the controll unit to burn out my pumps?



Thank you

Adam

<a href=showthread.php?s=&postid=15673208#post15673208 target=_blank>Originally posted</a> by rvitko
The osmolator has no system to detect if the pump is running dry, but the pump is not water cooled or lubricated and is not harmed by running dry for the brief time the controller allows the pump to run, after 10 minutes of running without a fill being registered the controller shuts off the pump. The pump is a simple low voltage DC hobby motor inside a waterproof housing with a direct drive shaft through a dual oring seal. Do you actually see signs the pump has melted and overheated? Are you sure the pump doesn't work and that it isn't an issue with the controller? The controller has a current limiter for the pump, if the pump draws too much power for the current limiter it cuts off power to the pump. If the wiring or connector is corroded or shorted or the current limiting switch is defective, these could all make it appear as if the pump is the problem, but it is not, the controller has cut power to the pump so it has enough power to run its basic safety functions. The older pumps had single seals (2+ years ago) these typically lasted 12-24 months. The new pumps use a dual seal and they last twice as long on average. The only thing that I have seen kill these pumps prematurely is kalk slurry, bits of plastic or gravel in the reservoir, or occasionally, a defect. If this osmolator is a couple years old, it likely has the 800mA current limiter, the dual seal pump will use 1000mA at 12V but will be under 800mA if the wiring is good and you use a 9V power supply. New osmolators use a 1200mA limiter and this is safe because the power supply on new osmolators can deliver 1600mA while old ones used an 800mA or 1000mA power supply, which will be fine so long as you stick to 9V, clean wire and 4-7 ft of head pressure (lower head pressure increases current draw). In short, if this osmolator is a couple years old, either stick to 9V and check your wiring and head pressure or, it needs to be sent in and have the current limiter upped and you need the new power supply.

 

[rvitko]

The pumps can handle up to 12V but in your set up with a new double seal pump you should use 9V to keep the amp draw below 800mA. I suspect that you had a pump go bad and maybe got a bad pump. I had a batch about a year ago that the impellers were drilled too loose so the shaft spun without engaging the impeller. I got about a half dozen like that. I think the problem you have now is the current limiter and 9V will solve this most likely.

 

[ataller]

Thanks Roger. The last two pumps I bought were purchased together so maybe they were part of a faulty bunch.

I will switch down to 9v, and with a new pump hopefully I won't have this problem again.


Thank you,

Adam