3155 osmolator sensor not recognizing low water

[OTB008]

Hello,

I noticed the other day my ATO is not turning on the pump when the water drops below the optical sensor. When I unplug and plug back in the to low light is red for a short time then it goes through the normal 15 seconds or so of running the pump. It then says the water level is ok even if it is not. I have cleaned the sensor and no change. I'm pretty sure the optical sensor is bad. Can the optical sensor be replaced?

Thanks,
Jared

 

[rvitko]

The optic sensor can be replaced, however, the most common cause is mineral deposits which will appear as a dull haze when the sensor is dry, they may be invisible when it is wet. I would try a roughly 2 hours soak in vinegar first. If this Osmolator was made after mid 2015, replacing the sensor is easy, it just plugs in, prior to that they are soldered.

 

[OTB008]

Ok thanks. I have dried it and cleaned it with vinegar but I did not let it soak so I will try that this evening. I purchased the unit a year ago but the sensor does not unplug from the display so it must be older than that. When I power it up after the four lights light up the too low light is red for about 15 seconds. Does this mean anything?

Thank you,
Jared

 

[rvitko]

That means it failed the self test, it would unplug inside the controller so you have to open it to see the plug. It can fail the self test though just from being very dirty, all the red light means is the voltage was less than half of what it should be.

 

[OTB008]

So I soaked the optical sensor in vinegar for 2 hours and let dry and the sensor is still not working. I am still getting the failed self test red light when I power up.

 

[rvitko]

If you have the plug type I can just send a new optic sensor, I would just need a copy of the receipt, if it is the solder type, I would knock it out within a day of getting it.

 

[OTB008]

I purchased on amazon and I have the invoice from that will that work? How do I identify the plug type? Thank you for your help.

 

[rvitko]

Yes, that is fine. Just undo the 2 screws on the back and open it, there will either be a white 4 pin plug or 4 wires soldered to the board.

 

[OTB008]

I sent you a DM with my address and the receipt. It is a plug in. Thank you for your help.

 

[Reeferdood]

Mine just kicked the bucket today.. I wonder if there is a way to bypass the optical sensor and just use the float switch for now?
i just ordered a new one and Ill send this unit to Roger for a back up...

 

[mmw64]

Mine just kicked the bucket today.. I wonder if there is a way to bypass the optical sensor and just use the float switch for now?
i just ordered a new one and Ill send this unit to Roger for a back up...

Roger is amazing. Best customer service bar none!

 

[Reeferdood]

Roger is amazing. Best customer service bar none!

Yes, I concur. I have spoken with him a few times, great guy.

 

[moustachio]

If you have the plug type I can just send a new optic sensor, I would just need a copy of the receipt, if it is the solder type, I would knock it out within a day of getting it.

Hey Roger I just found this thread, I have the same issue I have the tunze 3155 and I've tried cleaning the sensor and it still won't recognize low water. I unplugged it from the board and I'm just using the float switch to recognize it now. I've had this for two years now and it went down about a month ago. Can I order the sensor from you so I can use it again? Thanks

 

[Blu3Rav3n]

Hey Roger I just found this thread, I have the same issue I have the tunze 3155 and I've tried cleaning the sensor and it still won't recognize low water. I unplugged it from the board and I'm just using the float switch to recognize it now. I've had this for two years now and it went down about a month ago. Can I order the sensor from you so I can use it again? Thanks

Hi there @moustachio ! You can get with Tunze USA through the email [email protected] to get a replacement sensor. @rvitko is in Germany at the moment at Interzoo, but he will get back to you about a replacement soon. In case this hasn't been eliminated yet, the sensor does work with infrared light. Depending on if you have a refugium light/ grow light and where you have the sensor, it can confuse it.


Here is a video on our YouTube channel and the sensor is mentioned around 21:30

 

[rvitko]

Can you clarify how you are running it? Without the optic sensor there is nothing to turn the pump on, the float is only an emergency kill switch. If it is less than 2 years old it would be a warranty issue, I would need a copy of the receipt and the serial number. Optic sensors are replaceable.