Osmolator pump dying?

[GuySmily]

Hey Roger (and everyone else),

My osmolator stopped working last week. I was wondering if I could get some help troubleshooting the issue (or if I should just the whole thing in).

The pump sounds really weak when it runs, and it only flows a dribble of water into the tank before stopping. When it does run, it's a lot slower than it should be, sometimes increasing/decreasing in speed (occasionally putting out a good bit of flow for a second or two).

The controller box is also getting hot very quickly - feels like it's near the PTC that we replaced a year or two ago.

The system failed very suddenly - it was working perfectly one day, and had problems the next.

What kind of troubleshooting can I do on my own? Should I check for certain voltage/amperage measurements at the pump (before the PTC heats up)? Should I attempt to spin the pump using electricity from somewhere else, like a 9v or 12v battery?

Thanks
-Rusty

edit-
Here's a picture of the circuit board I snapped when I did the PTC replacement back in December 2011.

 

[rvitko]

The PTC is essentially a bimetallic circuit breaker, it gets hot and the contact separates if the pump draws more than 1200mA (800mA on older ones, but the picture shows 1200mA).

There are 3 possibilities and a combo of all of the below is possible.

1) The pump is dying, if it is more than 3 years old, this is a very safe bet and I would simply replace it.

2) The european terminal connector got wet and has corroded, this is the 4 screw connector for the pump. These are available at Radio Shack in a strip of 10-12, you will just cut off the 2 terminals you need.

3) The wiring from the controller to the pump, as well as the pump wiring, may have wicked in water, they then corrode and the resistance gets quite high, this will be visible if you strip back the insulation and it is black, you will need to cut back to fresh copper, I have seen wires that have 2ft+ of black wire, the more common is 4-8".

I would remedy this ASAP, a transistor on the board can also overheat and render the controller unrepairable if this is not solved.

 

[GuySmily]

It must be pretty ancient since it originally had the smaller PTC. Got some pretty good service life outta this thing considering I've used it for so long, for both ATO and water changes. Anyway, I unplugged the controller as soon I noticed the problem (when the 10 minute alarm went off), and I've only tested it for a few seconds since then, so hopefully the controller is still good.

No corrosion anywhere, so I guess I'll order a pump. I've been meaning to buy one of those magnet mounts anyway, so I guess this is my chance to order them both at the same time.

Thanks, Roger.

-Rusty

 

[rvitko]

I would hold off buying the magnet, if you end up needing a new controller, then the cost of a pump, controller and magnet holder excedes the cost of a complete osmolator. If you just get the pump, you will eventually need a spare pump so that is not a bad investment.