Osmolator 3155 Only Runs 30sec / Overheating

[GuySmily]

Hello,

I just bought a (used) Osmolator, and I found that the pump only runs for about 30 seconds before it shuts off.

I noticed that the control box was getting hot above the "Pump on" LED. I opened it up - since I wanted to change the alarm jumper anyway - and I found that the big blue thermistor was very hot.

I know I shouldn't have, but I plugged it in with the case off, and found that blowing on the thermistor (cooling it down) made the pump run faster. (I guess that's a "duh" statement, since that's what thermistors are for)

Any tips on what might be causing this to happen? I was trying to refill about 2.5 gals of salt water into the tank - quite a bit more than what I'd lose from evaporation - but my understanding is that the pump should be able to run for up to 10 minutes (which is when the "Too low" light should turn on).

Thanks!

 

[rvitko]

I would assume the following scenario-

The controller is an older unit, pre 2007 and has the 800mA PTC (blue component), it is dime size and will only work with the newer double oring seal pumps at 9V and if the connection is perfect. At this time the osmolator pump had a single oring seal and the power supply was 9V or switchable between 9 and 12V, a new pump can run on an old osmolator if switched to 9V and the wiring to the pump is free of any corrosion or salt creep.

A newer osmolator has a 1200mA PTC, it is roughly penny sized. It is bent nearly flat against the board vs standing upright. In late 2008 the pump was upgraded to a double oring seal for better durability and we switched to a more compact 11V power supply.

The options are, send it in and upgrade the PTC, the wiring to the pump and connector for the pump should also be thoroughly inspected (cut back until shiny copper is found, retinned and with a new euro connector terminal) and upgrade the transformer if it is the old style.

Or, make sure the wiring is clean to the pump as described above, run it at 9V, at with a greater than 3ft head pressure, higher head reduces the pumps power consumption.

It is a remote possibility the pump is simply failing.

 

[GuySmily]

Yep, it's a blue PTC C955 just as you described. The pump was replaced just prior to my buying the setup, and it's in pristine shape.

The very top of my tank is 4ft off the ground (less distance between water level of RODI jug and tank), but I still had issues - probably not enough pressure.

Assuming the PTC is the only component to replace, could I do it myself? I'm an engineering student, and have no problem soldering. I figure it would cost less to ship a small component one way than to ship the whole box + wiring + sensors both ways.

As far as the pump wiring goes, I was thinking about ditching the euro terminals and installing a waterproof (automotive) connector. Is there some reason you guys used the barrier strip instead?

I JUST found this post explaining the same situation. It's awesome that you guys are doing this instead of saying "sorry, out of warranty - go buy a new one." :thumbsup:

Do I need the new power supply? I would definitely appreciate the smaller size but won't bother if it's optional. Pumping speed certainly isn't an issue.

 

[rvitko]

I can send you the bigger PTC, just PM me your address.

We have actually switched away from the euro terminals, waterproof automative connectors are too costly for our use, especially since every spare pump would need one and this would add probably $2 or more to every spare pump. We have switched to a specialty quick connect used in emergency back up lighting for the battery connection, but this is not easily retrofitted as it comes as a pig tail that solders to the board in place of the wire that is there now. You can certainly change the connector, just keep in mind the pumps last 2-3 years so you will have to transfer the connector every time.

Here is the reason you may need a new power supply, same reason for the PTC problem:
The single oring seal pump drew 700mA at 12V and 550 about at 9V, the double seal pump needs 750mA at 9V and 1100mA at 12V. The power supply you have is rated for either 800mA or 1000mA, we used a couple over the years. Either is fine at 9V, but at the 12V setting on the switchable 800mA one that was used from 2002-2006, you could overload the power supply and burn it out. In late 2006 and 2007 we switched to a fixed 9V 1000mA power supply.

 

[GuySmily]

Will send you my address in a minute. Much appreciated!

I hear ya about the connector cost. Luckily, I'm a car guy, so I have this stuff laying around. I don't mind soldering and heatshrinking a couple wires every 2-3 years.

As for the power supply, I'll have a peek at the rating when I get home, but I'm assuming it's the old model since it has the giant round part around the plug. Not too expensive to replace, right? (Will PM you)

 

[GuySmily]

Finally got around to putting in the new PTC. Works great now. Thanks Roger! A million thumbs up to you and Tunze.

 

[GuySmily]

(RC likes to double post even if I only click once)

 

[rvitko]

Thanks!