Tunze 3155-optic sensor not working

[JasonK84]

I just started up my system today and was getting water levels and salinity dialed in to start cycling. I set the sensor and float switch where I want the level to be and plug it in. It starts filling even if the optic sensor is under water and continues to fill until tripping the float switch. This is a brand new unit ordered through BRS. I've tried starting with the sensor above water and still it fills and covers the optic sensor and keeps pumping until the float switch shuts it down and sets off the high level alarm.

I also searched on-line and found a video of someone having the exact problem I'm having. Is there a fix for this or is it a faulty unit?

 

[Water Dog]

It’s hard to see in the video, but it sounds like it could be a siphon issue. Is the water level of your ATO reservoir above the outlet of the ATO hose? If so, it’ll siphon.

 

[WVNed]

If the pump is running until it trips the high level float sensor I would say it has a problem.

 

[JasonK84]

It’s hard to see in the video, but it sounds like it could be a siphon issue. Is the water level of your ATO reservoir above the outlet of the ATO hose? If so, it’ll siphon.

Nope, if it were a siphon issue it wouldn't shut off with the float switch. Besides, you can still hear the pump running.

 

[JasonK84]

If the pump is running until it trips the high level float sensor I would say it has a problem.

Agreed

 

[TheHarold]

I think you are not powering it on with the water level far enough below the optical eye. The optical eye detects a “change”, not whether it is submerged or not. If it is submerged and powered on, it will add water until it hits the high level switch. Try it with the water level even lower perhaps, so that it can add a bit of water and then cut off when it hits the optical switch.

 

[Water Dog]

Also note, when powered on, the 3155 will automatically run for 15 seconds regardless of the water level in relation to the optical eye.

 

[JasonK84]

I think you are not powering it on with the water level far enough below the optical eye. The optical eye detects a “change”, not whether it is submerged or not. If it is submerged and powered on, it will add water until it hits the high level switch. Try it with the water level even lower perhaps, so that it can add a bit of water and then cut off when it hits the optical switch.

So how will that work after a power outage and starting off under water.

 

[JasonK84]

I just hooked it all back up in my kitchen sink to test again but got the same result. I'll try again with it higher above the water and see if it will shut off.

 

[TheHarold]

So how will that work after a power outage and starting off under water.

Unfortunately, exactly how you imagine it will. As @Water Dog said, the Tunze 3155 automatically turns on for 15 seconds regardless of water level when powered on. If it is submerged before that 15 seconds is over ,it will not know. It keeps adding until it hits the emergency switch and alarms.

I do not have that issue because I use mine with an apex controller on a battery backup. If power goes flickers, the Tunze outlet is forced to stay off for two hours before turning on again.

 

[WVNed]

If mine is powered in a high water condition it alarms but the pump does not run even when the water level drops and clears the alarm.

I have it plugged into a power strip with other pumps and turn that strip off to do a water change. When I turn it back on the drain back is in the sump still.

 

[mmw64]

I just started up my system today and was getting water levels and salinity dialed in to start cycling. I set the sensor and float switch where I want the level to be and plug it in. It starts filling even if the optic sensor is under water and continues to fill until tripping the float switch. This is a brand new unit ordered through BRS. I've tried starting with the sensor above water and still it fills and covers the optic sensor and keeps pumping until the float switch shuts it down and sets off the high level alarm.

I also searched on-line and found a video of someone having the exact problem I'm having. Is there a fix for this or is it a faulty unit?

Roger at Tunze Inc. who happens to be in Texas is really helpful.

 

[JasonK84]

If mine is powered in a high water condition it alarms but the pump does not run even when the water level drops and clears the alarm.

I have it plugged into a power strip with other pumps and turn that strip off to do a water change. When I turn it back on the drain back is in the sump still.

Also note, when powered on, the 3155 will automatically run for 15 seconds regardless of the water level in relation to the optical eye.

Roger at Tunze Inc. who happens to be in Texas is really helpful.

I just tested 1 more time in the sink and a 5 gallon bucket and confirmed the unitis operational when started above the water line. I also just tested the feed mode on my current USA loop return pump and wave pumps and it appears the return doesn't slow down during that keeping the return chamber stable. It was going to be real annoying if I had to listen to that ringing for 10 minutes everyday. I'll hook it back up and give another chance.

Thanks for everyone's input here as I was at a complete loss.

 

[rvitko]

This is the most common causes below: I don't see any reason to believe it is a siphon by the info you provided. I suspect it is bubbles on the sensor. When brand new the sensor is a bubble magnet, this takes 3-5 days to solve itself as a biofilm builds up on the sensor. It is critical though to minimize sources of bubbles and particularly never have the top off hose by the sensors. Keep in mind you have 2 user settings inside the controller, you can turn off the alarm and you can turn the pump speed up or down.


1) A siphon, if it is a siphon the issue will be seemingly random, it will tend to only occur when the reservoir is full and the water will fill to a level possibly above or just below the float. Siphon situation 3 is the most probable cause but note as shown in 4 that a loop will not solve it, the end of the hose must always terminate above the reservoir water level.
2) A sensor issue. The first test is to use the self diagnostic test on the Osmolator to verify the sensor is in working order.
1) With the sensor completely wiped dry, plug in the controller. The sensor MUST be clean and dry for this test to work, a wet or dirty sensor will always fail.
2) All 4 lights will flash and it will beep, a single light will show for 1 seconds and then the normal 15-20 second pump run at startup will begin.
3) This light that is on one second is the optic sensor status, green means pass, yellow means it is marginal, red means it failed.
Assuming it passes the self test the issue is bubbles, optic sensors work by detecting the refraction of air vs water and make no differentiation between a bubble or being dry. The most overlooked source of bubbles is placing the top off hose in the vicinity of the sensors, the incoming splash will introduce bubbles and cause a fill. The hose can be routed to any area of the sump or main tank, and the optic sensor must be in a calm and bubble free area. A definitive test to verify bubbles are the cause is if you can catch it in the act of an overfill and wipe your finger across the sensor and filling stops within 5 seconds, the cause was bubbles.
3) There is a 3rd possibility but this is relatively obscure and only will apply to tanks under 50 gallons or due to a misunderstanding of how the Osmolator works. The Osmolator has timed functions in addition to sensor controlled functions and for the first 25-30 seconds it is not actually detecting water levels and is instead running a series of self diagnostic tests. The pump will always run for 15-20 seconds when you first power it up, this is so the installer can verify the pump is operational and the pump and tubing are primed and ready to fill. Also, the Osmolator always waits 5 seconds to fill to account for waves and surface movement and overfills for 5 seconds so the pump is cycled on less often. If the tank is under 50 gallons you need to open the controller and reduce the pump speed to “nano” and if it is under 30, an additional restriction such as a drip irrigation valve might be needed, this will reduce the amount of water added by these timed sequences to avoid raising the float.

 

[JasonK84]

This is the most common causes below: I don't see any reason to believe it is a siphon by the info you provided. I suspect it is bubbles on the sensor. When brand new the sensor is a bubble magnet, this takes 3-5 days to solve itself as a biofilm builds up on the sensor. It is critical though to minimize sources of bubbles and particularly never have the top off hose by the sensors. Keep in mind you have 2 user settings inside the controller, you can turn off the alarm and you can turn the pump speed up or down.


1) A siphon, if it is a siphon the issue will be seemingly random, it will tend to only occur when the reservoir is full and the water will fill to a level possibly above or just below the float. Siphon situation 3 is the most probable cause but note as shown in 4 that a loop will not solve it, the end of the hose must always terminate above the reservoir water level.
2) A sensor issue. The first test is to use the self diagnostic test on the Osmolator to verify the sensor is in working order.
1) With the sensor completely wiped dry, plug in the controller. The sensor MUST be clean and dry for this test to work, a wet or dirty sensor will always fail.
2) All 4 lights will flash and it will beep, a single light will show for 1 seconds and then the normal 15-20 second pump run at startup will begin.
3) This light that is on one second is the optic sensor status, green means pass, yellow means it is marginal, red means it failed.
Assuming it passes the self test the issue is bubbles, optic sensors work by detecting the refraction of air vs water and make no differentiation between a bubble or being dry. The most overlooked source of bubbles is placing the top off hose in the vicinity of the sensors, the incoming splash will introduce bubbles and cause a fill. The hose can be routed to any area of the sump or main tank, and the optic sensor must be in a calm and bubble free area. A definitive test to verify bubbles are the cause is if you can catch it in the act of an overfill and wipe your finger across the sensor and filling stops within 5 seconds, the cause was bubbles.
3) There is a 3rd possibility but this is relatively obscure and only will apply to tanks under 50 gallons or due to a misunderstanding of how the Osmolator works. The Osmolator has timed functions in addition to sensor controlled functions and for the first 25-30 seconds it is not actually detecting water levels and is instead running a series of self diagnostic tests. The pump will always run for 15-20 seconds when you first power it up, this is so the installer can verify the pump is operational and the pump and tubing are primed and ready to fill. Also, the Osmolator always waits 5 seconds to fill to account for waves and surface movement and overfills for 5 seconds so the pump is cycled on less often. If the tank is under 50 gallons you need to open the controller and reduce the pump speed to “nano” and if it is under 30, an additional restriction such as a drip irrigation valve might be needed, this will reduce the amount of water added by these timed sequences to avoid raising the float.

Very informative! I actually re-installed on the tank late last night and was able to get it going. I do think bubbles were part of the issue as well as starting the sensor under water since I didn't want the level any higher. It is working at the moment and I am certain it was a matter of human (me) error.

 

[rvitko]

Thanks for the follow up, just let me know if you have any further issues.

 

[Rjramos]

Very informative, thanks! I just installed mine last night and was having the same exact issues.[emoji1303] I shut it down and will get it going tomorrow.

 

[JasonK84]

Very informative, thanks! I just installed mine last night and was having the same exact issues.[emoji1303] I shut it down and will get it going tomorrow.

Glad it helped you. Mine has been working flawlessly since getting this issue corrected.

 

[Rjramos]

Still overfilling, float stoped it then high alarm ringing, then low alarm. I restarted it today and it was working perfectly, I come back about 1 hr later and the optic sensor is submerged and float switch up, high water. I left it since with the float activated, came back and then it says, “too low blinking”with the optic sensor submerged. Also showing too high and level.

Ayou can see in the picture, no bubbles and calm water in the sump. I read somewhere cleaning the new optical sensor with detergent, could this be the solution? I was also thinking of moving it to another place.

 

[JasonK84]

Where does the incomming freshwater dump? If it's close to the sensors it could be causing some micro bubbles from splashing close by. I have mine dumping in the chamber prior to the return section.
I do notice some tiny bubbles on the under side of your float switch. If they accumulate on the optic sensor it is probably the cause.