Tunze Osmolator 3155

[jmoose]

I have a Tunze Osmolator with a 5017 controller. I get a low water alarm (yellow led) but the pump will not come on. With the yellow led on, I get no voltage on the output to the pump. I took the back off the controller to see it there was a reset switch. No such luck. Anyone have any hints?
Also, there is a disc capacitor on the board (its blue), that gets very, very hot.

 

[rvitko]

That blue component is the PTC, it is a thermal switch that kills the pump if the pump draws more than 800-1600mA, we have used three configurations over the years. 800mA, 1200mA and 2 800mA. This component prevents an excessive draw by the pump from starving the controller for power causing it to be unable to run critical safety functions. If this component is hot and "open" so current is not reaching the pump, the cause can be as follows-

1) Corroded wires or connectors.
2) Very short hose run with low head pressure (the pump draws more power with less head pressure)
3) New pump on old controller, new pumps have a double seal and draw 800-1000mA, old pumps had a single seal and drew 600-800mA. This change was made about 1.5 years ago. The new pumps will work on older set ups but only with 9V which lowers the current draw with an 11 or 12V power supply they can open the PTC depending on the above conditions.

 

[jmoose]

Thank you Roger.

The connections look good, not corroded at all. The hose run is ~3 feet vertical. Im guessing maybe I have a new pump on an older controller. I will try running the controller on a 9 volt power supply and see what happens.

 

[rvitko]

You can also send it in and I can upgrade the PTC, you might also try cutting back the wires, if the sat in water at any point I have seen them wick water all the way back into the controller and they get really black inside with oxidation.

 

[jmoose]

I will check the wires. If upgrading the PTC only requires desoldering the old one and soldering the new one back to the board, all I would need is the new part. I have ordered a new pump, just in case.
Do you think changing the supply voltage will work?

 

[rvitko]

It might but technically the better solution is the PTC. We would just be soldering a second 800mA limit PTC in parallel with the existing one. I can send you one if you prefer, it is fairly simple if you have a fine tip soldering iron, Just work hot and work fast to avoid overheating the board.

 

[jmoose]

pm sent.