Testing tank sensors

[imnprsd]

Can any one tell me what these "orange" things are going to my gray and black holding tank?

[imnprsd]

Update:

INSIDE HOLDING TANK DISPLAY

* My fresh water has always worked.

* My gray tank levels used to read okay sometimes, but now seem to be reading okay in genera. (I need more time to monitor it.) But I think cutting and connecting the inside LED Display ground wire to a good "chassis ground" and not to the battery ground.

* My black tank levels are all over the map. One day they are full and another day they are empty. So no change here after the ground wire modification.

OUTSID HOLDING TANK DISPLAY

* Fresh, LP ==> Okay. No change.

* GRAY & BLACK TANK LEVELS ==> Never worked well and still don't.

NEXT STEPS

* I don't have a good wire diagram for starters. Winnebago files are not accurate and say very little about the so called "red board upgrade". This probably is because I am trying to fix a problem that has been around for 20 years and no one has tried to build a better mouse trap in the last 10+ years. So the odds are against me for sure.

* If anyone know how the remote Ventline Holding Tank Display in the dump station area talks to the main circuit board, please let me know. And if yo have any wiring schematics please share them with us all.

* I have not added any diodes per the instructions when Winnebago recommend using those glue-in-sensors.

* I may try experimenting with the addition of an amplifier in the circuit.

Note: The fact the fresh water and LP sensors and display works properly, and always has, suggests the LED lights will illuminate if I can boost the current. (TBD)

* I still don't know what those "orange things" are in the picture below. Can anyone tell me?

* And if all this does not work, and I have time in my Montana camp spot, I may take my OEM "green" circuit board to a local TV repair shop who last year fixed both my VDC (air tank senor circuit board) and my Dimensions Inverter. So maybe this year he can figure out to help us all get our gray and black holding tank level sensor to work more reliably.

PS
That orange thing wax looking stuff is sticky like honey? What's is it? And what's it do?

[aw2657]

This is the best write up I have seen on the dreaded Winnebago tank sensor errors. And the best part it.....I have the exact same coach that I have been struggling with for a while now. I was finally able to get the gray tank sensors fairly accurate inside and out. The fresh water sensor is accurate outside but the inside seems to show a little more water and jumps quickly from 2/3 to empty but I have learned to live with it. The black tank sensor is where I have the strangest issue. I have cleaned and cleaned my tanks with everything known to RV'ers so I'm pretty sure it's not a dirty tank/sensor issue. And the symptoms I'm having lead me to believe it has something to do with the wiring or diodes. The black tank goes from empty directly to full. All the lights work but it is either reading empty or all the lights for full and sometimes I can get the 1/3 and 2/3 lights to flicker if I get the water level in just the right spot while cleaning/flushing the tanks. Based on the drawings...all of the grounds are tied together so my ground should be good. I'm thinking the problem is either in the 1/3 and 2/3 sensor itself or in the wiring of those two. Has anyone see something like this before? I'm assuming that the sensors are not dirty because if they were they would be lit up when it's empty but they are off until the tank gets to full and then they are activated. Any thoughts or ideas of where to start would really help me dig into this issue. Next step is pulling off the paneling to get to the black tank sensors and start testing. Thanks!

[imnprsd]

I'm 1-2 weeks from arriving at my Montana camp spot where I will have 1-2 months to get around to this project again.

My gray water sensors work somewhat reliably, but never the black.

So if the Circuit Board components are the same for all tanks, and I'm sure they are; and if the principle of lighting-up each LED on the display is based on the summing of resistors (ohm), and I'm sure it is, then the problem is a)
conductivity or b) too low of current or c) both.

What if the sensors oxidize in the tank over time and this too affects the conductivity. I.e., scaling and/or oxidation would create an "open circuit" and that is pretty much what we get.

Or the current is too low to penetrate the "muck" in the black and gray water tank. So to attempt to fix that I'm going to try boosting the the voltage and current thru the black and gray water tank probes and see what happens.

I hope if I just boost it enough the Circuit Board will receive this information and start to work.

My guess it that the so called "red board" just increased the voltage by adding an amplifier to the line; but that added "noise" which then they tried to solve by adding diodes to block the AC transients... which did not work. So I'm going to try adding an adjustable voltage regulator that also lets me monitor the amps in the circuit... and see if that wakes the circuit board up... and more accurately lights up those LEDs on the panel to indicate tank fluid levels.

COMMENTS

* I think the fresh water sensors are physically different than the gray and black water sensors.

* I think the black water tank "muck" does not conduct as well as fresh water, so the CB can't get a good signal. And since we are talking about V=IR, and R is constant and V is constant, I'm going to try using a Boost Buck Converter, DROK DC 5.5-30V to 0.5-30V 5V 12V 24V Adjustable Power Supply Regulator Module, and see if more amps applied to the black and grey tank will help the CB differentiate one tank level from another.

Here's the link on amazon:
https://www.amazon.com/gp/product/B0...ustomerReviews

I don't know what to expect. And I'm not that good on the bench. So if anyone out there advises me not to do this, please speak up.

When I get to Montana there is a TV repair shop guy I got to know and I think he will be willing to take on these type of eccentric project fix.

So hopefully, he can help me figure out how to get the LEDs lighting up on my holding tank display panel.

Note: The fundamental problem is that the integrated circuits on the CB are 5V =/1 10%, so it's know like we can boost the line current out of the DROK and expect favorable results on the holding tank LED circuit board, which I think use comparators to built a truth table of sorts that light up the LEDs one at a time... and then we see that LED TREE as being the level in the tank.

So I will post an update as soon as I have one.

PS

I still don't know what those ORANGE THING ARE that connect to the holding tank probe wires? Can anyone tell me? This is very important. What is that very sticky, bees-waxy like stuff inside the orange blub below?

[Wyatt]

If you remove the wires off of the sensors, the tank should read empty on the panel. If not, it’s not probably the sensors, unless your sensor wires have a short.
I noticed this when I replaced my sensors.

[aw2657]

I love your thinking IMNPRSD... I can totally follow it but have one question just to prove my issue against the theory. I'm showing only an empty light on my black tank when it's empty as well as up to 2/3rds. Then it jumps immediately to Full with all lights on. So empty registers correct and full registers correct. But if the sensors were dirty or the was an open circuit condition on the 1/3 and 2/3rds sensors.....the lights should stay on. So the fact that they are off until the tank goes full and then they all come on stumps me. But It does sound like boosting the senor or changing it out to one that works might be a first step. Does anyone know if there is a direct replacement for the ones used in the factory system? My setup looks exactly like your pictures above. Thanks!

[jeepster13]

Same thing just happened with my Adventure. I was able to trace it down to the switches for black and gray water not having power. There was a break in the copper on the circuit board between CR4-CR8. I just soldered a jumper wire between the broken copper and all is good now.

Please let me know if you want me to forward pics.

[aw2657]

Thanks Jeepster! I'm thinking my switches have power because when I push it all the lights will light up. It's just the 1/3 and 2/3 lights that only light up when it's completely full. Is that the same issue you had and fixed by soldering the circuit? If so I would love to see some pictures so I can check my circuits. The other strange thing is the panel on the outside shows the same as the panel on the inside when this happens. Both of them work off of different switches so I would think it's tied to what the boards are seeing from the sensors. If the boards showed different.....then I would think one of the boards was bad. Just by thoughts.....

[jeepster13]

Mine was doing the same thing in the first post.

[imnprsd]

Does anyone have a schematic for the outside display panel?

Also I wonder if the panel inside the coach will start reading more accurate if we disconnect the panel outside the coach inside the Water Station Bay?

... Maybe removing power to that outside panel will help the main CB output correct tank level indications?

... probably not since the LED lights up bright, but what I'm trying to get at is if anything is pulling down the current that goes to the circuit board comparators.

... more likely it is a circuit board voltage problem and maybe some cold solder joints are the first thing to check. That sounds like a good call.

Did you have any trouble removing the circuit board from the inside display? ... my large panel seems to be rather stuck in place.

Also, has anybody disabled the outside display to see how that affects the operation of the panel inside the coach?

Last but not least, I'm still wondering what those orange bulb like things are next to my gray and black tank sending unit?

[Morich]

I've not looked in on this questions as feeling I had little to offer due to my unit no longer using the probes to go inside but the flat pads, which throws all my finding out the window for your system.

But I do see one question that I think I do know about, even though pretty small!

The orange "thingie"? I would say you system has had some mods made in the past and those are just a different form of the common electrical screw connectors only somebody went "deluxe" and went with filled connecters like one would use in buried or super wet conditions. Kind of strikes me a something the fellow uses at work and follows him home for other uses???

What makes the "best" connection often comes down to what is on hand, so in my case, I like more long lasting and hate the way screw connectors can back off on things that get lots of jarring like RV, so I go for cutting screw connectors of and solder as I always have it on hand and I do trust it not to come apart or get corrosion between the wires if I do a good solder joint.
Just different strokes for what we each have found suits us better. If I was into fast and production the crimp connectors are good for getting it out the door and certainly keeps business rolling back in to fix the ones which corrode and go open!

[jeepster13]

[imnprsd]

Morich: Thanks for you explanation of that "Orange Thingie." I'm guessing you are right. That bees wax is to encapsulate a splice or connection so it does not oxidize later. (Pretty smart, but I'm guessing my circuit problems lie elsewhere.)

* What I can't tell is if my probes are OEM or replacement probes? My current probes have a screw to hold the wires and other OEM probes I have seen use nuts.

jeepster13: Thank you for posting pictures.

* Were you able to see cracks in the solder traces?

* Also, are these bypass capacitors to ground? ...Used to filter out noise?

==> I see a transistor on the board too. ...And a trim-pot I think that is used to calibrate the empty level of a tank, but I'm not sure.

* Do you know what the function of the trim-pot is for?

* Do you know how this circuit board distinguishes between different resistor values?

* Do you think all these board problems are voltage related? ...Which means there is not enough current in the circuit for the CB to work properly.

... or do you think the problem is with the probes? ...which I see as just bare wires trying to use water or "muck" to complete a circuit and increase the resistance along the way.

I.e., as the tank level rises, another resistor is added to the circuit and that drives down the current to the circuit board.

So how does the circuit board measure the change in current? ...Or does it use comparators to build a digital truth table (output) to light the individual LEDs?

[imnprsd]

These last few days I have been studying and modifying my existing 2004 Itasca "Horizon" 40AD holding tank sensor board(s) and this is what I found after I took the boards out of their respective housings.

* I have the Ventline "Green Circuit Board" in my early model 2004 Horizon, and I saw no modifications to the circuit that I could detect. However, it would appear before my ownership someone may have replaced the BLACK & GRAY sensors. (Probably, because this was the scuttlebutt going around on how to fix the inaccuracies of your Black & Gray water tank. And I'm guessing this was a Red Herring.)

* The inside circuit board I found several "cold solder" or "cracked joints" to all of those Solar Circuit diodes used to light-up the small OEM engine battery Solar Panel on the roof. (Which was another stupid selling point back in 2004 and which turned out to be useless.)

==> Now I can't tell you why my BLACK & GRAY sensors started to work accurately after fixing these cold solder joins, but that's what happened.

==> My only guess is that the cracks in the solder joins interrupted the power to the circuit board, which is to say it affected the current to the Holding Tank Sensors, and therefore the LM339 Comparator could not do it's job. (Just a guess. I'm not a board tech. Maybe someone out there can tell us what they think.)

Note: All system-circuits (Black - Gray - Fresh Water - LP) are separate, but they all share the same power and ground; and maybe those diodes cold solder joins put some noise on the line that interfered with the LM339 Comparator, which may have been enough to get erroneous readings on those LEDs? IDK. ...Maybe someone out there can confirm or deny this possibility?

==> All I can tell you is that by repairing the cold solder joints to the Solar Circuit, it also fixed the inaccurate GRAY tank sensor.

BLACK TANK SENSOR DIAGNOSIS AND FIX

* I examined the wires to the "FULL" sensor in the BLACK tank.

* I confirmed the sensor readings were 66K-ohms between the sensors and 133K-ohms across both the sensors. (This is from the empty sensor to the full sensor.) Therefore, I knew my tank sensors were good.

* I then chose to replace the BLACK tank "FULL SENSOR" wire connection by cutting off the ends and attaching new connectors.

* I replaced the ground connector too.

* Then I cut off that "orange encapsulation" thing in the picture above and joined all 3 wires together. I used heat shrink tubing and black tape for an extra moisture seal.

==> So... between the cold solder joint fix & replacing the Black Tank wire ends-connections at the FULL SENSOR and the GROUND SENSOR, my black tank LEDs are now reading accurately!!!

OUTSIDE CIRCUIT BOARD FIX

* The outside circuit board is exposed to water and outside humidity. In my case, the circuit board had some corrosion and acid issues that needed to be cleaned.

* The 2 trim pots on the CB for the GRAY & BLACK circuits were also frozen at ~100 ohms, which is terribly out of spec. As a result, the LEDs were consequently not reading right.

===

The pictures below will give you a good idea on what you may find in your RV, but I'm afraid I can't say exactly how this circuit works?

(Below I diagramed the GRAY holding tank circuit, which is identical too the BLACK holding tank circuit, and Fresh Water circuit too. I also listed my measured "ohm values" so you can have a reference if you decide to go this route.

* Adjusting the trim pots may or may not help. The idea is to "Increase Sensitivity" ...but in reality you need to compromise... on when you want your FULL LED to come on vs. the first indications your holding tank is 1/3 full.

It's not that accurate so don't worry if you can't remember where your pot was set before you started adjusting it. I found that if you empty your tank... and then fill it to where you think the 1/3 LED should light up, then that's where I would adjust the sensitivity, so the 2nd LED will come on, and that is were I would leave it.

...Then you can fill the tank all the way up to verify the point the FULL LED light comes on... and after that you will know approximately how much more water you can add to your Gray Tank before water starts percolating up from the shower P-Trap.

SUMMARY

1) I re-flowed the "cold solder joints" on my main circuit board inside the RV.

2) I reset the trim pots to the ohm levels shown in the picture below.

3) I cleaned the outside connectors... replaced both trim-pots for the GRAY and BLACK tank circuits.

4) I replace the wire connections for the "FULL SENSOR" and the "GROUND SENSOR".

5) I cut off the FULL SENSOR "orange encapsulated wire thing" and joined 3-wires together, and then used shrink tubing and black tape to protect the bare wires from moisture.

===> AND NOW MY GRAY & BLACK TANK LEDs ARE READING ACCURATE AGAIN!!!

NOTES

* If you can measure 66K-68K ohms between your sensors, with 133K-ohms from the "Empty" sensor to the "Full Sensor," then your sensors are working and you probably do not need to replace them.

* Ohm measurements from the ground tank sensor to the other sensors (1/3, 2/3, and Full) should be taken without any water in the tank. These readings can vary a lot, but sometimes there is a pattern you can detect.

Basically, FULL is more ohms than 2/3rds... and 1/3rd tank ohm readings are the lowest... when measured from the GROUND sensor.

I don't have enough experience to explain how this basic fuel gauge circuit works, but I will take a stab at it:

* As the tank fills, the tank sensor completes the circuit, and 66K-ohms is added at 1/3 full and again at 2/3 full.

* And since V=IR, as you increase resistance in the circuit, while maintaining a constant voltage, then "I" (current) must go down.

* The change in current is detected by the 4-stage, LM339 Comparator, and at each stage the 4 LEDs light on the circuit board one-by-one.

The function of the comparator is just a "logical switch" that passes current to a transistor, which in turn lights the LED. ...And as more LEDs light-up the markings on the display panel tell you what the tank level is.

Notice: All the resister values are very similar and easy to probe for accuracy. Of course, resistors don't fail that often; vs. some types of capacitors that always fail over time, but my caps were fine even after 17 years.

CIRCUIT ANALYSIS

In the GRAY HOLDING TANK CIRCUIT below there is a negative voltage loop and a positive voltage loop. However, I can't give you a summary on how this thing works, because that knowledge is above my pay-grade. ...Perhaps someone out their can make heads-or-tails out of it?


When it comes to Winnebago diagrams for the Ventline holding tank circuit, even over 10+ years, Winnebago seems to have dropped the ball on this one.

No wonder no one has fixed their holding tank circuit. Then Winnebago came out with cheaper to install "Contactless" sensors you paste on to the outside of the tank...

Then they came out with the so called "Red Board" which confused everyone even more...

And when the cost of repairing the BLACK & GRAY circuit got to be $500 or more, and coach warranties expired, everyone just stopped trying to understand how to fix their holding tank display problems, because the FRESH WATER AND LP level sensors were the most important. ...And the Ventline circuit board has worked perfectly for 20+ years for the FRESH WATER and LP circuit.

...Then the 50/50 myth about bad sensors soaked up another 10 years of scuttlebutt; when all the while I think the circuit board just needed fixing; and you need to change the ground so the tank sensors and the circuit board use the same chassis ground.

I'm still would like to know the principle behind this resistor ladder, and how the comparator, can be stabilized by adding a DROK if that is an option to the BLACK & GRAY SIGNAL WIRES?

WHY?

Answer: I think the accuracy of the circuit is dependent on keeping the voltage stable and maybe the DROK will help in these regards? IDK. I'm hoping MORICH or Cbeirl (just to name a few) can figure out how to build a better mouse trap as it relates to these Ventline circuit boards?

[imnprsd]

Based on my board fix, I believe most Winnebago holding tank sensor failures can be traced to the main Ventline L5113-03 (Green Circuit Board) and the cause of the failure (and fix) is to repair those cracked solder joints (aka cold solder joints) on all those diodes which are part of the solar panel circuit.

Note: All of the LEDs are an a separate circuit, but all of these circuit share the same power and ground. So cold it looks like diode solder joins on the power circuit will affect the ability of the comparator to do it's job; and in this state you will get sporadic LED lights; due to noise on the power line caused by these cold solder joints. (And diodes that can't do their job.)

So as explained STEP #1 is to repair your main Ventline Circuit Board.

In my case, STEP #2 was to cut out a bad black tank sensor wire connection.

And STEP #3 is to drill some holes in the face panel(s) so you can adjust the Trim-pot on the circuit board.

Take a close look at the metal face plates in the pictures below and notice where I drilled some holes so I can access the circuit board trim-pots after I re-install the board. This is the key when it comes to fine tuning your holding tank levels.

Note: I might be possible to drill the holes without removing your Ventline circuit boards, but you would need to go slow and be careful... not to drill too far!

GENERAL OBSERVATION

I would guess that 98% of all Winnebago owners who have a Ventline Holding Tank Circuit Panel... have NEVER relied on their Gray Water & Black Water holding tank LEDs to display accurate levels.

Therefore, I doubt adjusting the trim-pots alone will be sufficient to fix inaccurate readings. I.e., you probably have to pull the CB and get it repaired, but you can try drilling some holes in your face plate, like I did, and see if that works. ...I'm guessing 90% of you will not be successful.

So good luck and now we know how to fix our holding tank display LEDs if we want to. And now that you know what to do, please let us know if you too were able to get your holding tank LEDs working again?

Note: The holes I drilled are slightly offset to ensure the "F" is not erased from view. I.e. they are not directly over the trim-pot, but you can still turn it with a small screw driver; and you really can't tell the hole is there after you use a black marker.

[imnprsd]

I hope this will be last forum entry on this subject. And I would like to clarify a few things now that I have studied how the comparator works and what you can do to bring your green or red Ventline Holding Tank Circuit Board back to life.

First, we know the fresh water LED reads accurate. So, that tells us the voltage regulator is functioning, but how well it's functioning is another story.

And we know the fresh water tank sensors are of a different type vs. the black and grey tank sensors (fortunately). Therefore, we want to look elsewhere on the circuit board for problems, even though having a "stable & clean" voltage sources is required.

PROBLEM #1

I found the cold solder joints on the solar power LED section of the circuit board. I elected to re-flow the solder, and it helped a lot to get the entire holding tank CB to work better on the gray and black tank, but I would recommend you just disconnect this power & ground connector to turn-off this part of the CB, because who cares if the Solar LED lights or not. And I'm guessing your 10A (very small) solar panel does not work any more anyway.

PROBLEM #2

The ground to the circuit board needs to be changed from a battery ground, like it comes from the factor, to a chassis ground. And in previous posts I tell you has to do this. Note: Finding a good chassis ground means you need to ground the CB to the steel frame or find another chassis ground.

PROBLEM #3

On the black or gray stack of LEDs... if any stack of LED all light up at the same time, then I would say your resistance in the circuit is too high and there is not enough current for the comparator to work.

Solution: Take your CB out from behind the panel and lower the resistance in the circuit by turning the trim-pot to the right.

Note: It's looks complicated at first, but once you snip some of the ties, and undo the rats nest of wires, you can get to the back of your power panel very easily. TIP: Use a boot shoelace to hold the weight of your power panel, and just let it hang in place, by tying the panel to the top-hole on the right side of the wood back panel.

==> Now drill some holes in your LED faceplate so you can later adjust the trim-pot after you remount your CB to the panel. For hole locations you an refer to the posts in previous threads so you don't drill out the the faceplate markings.

==> Remount your CB and then adjust the trim-pot with a small straight-edge screwdriver... based on 1/3 water levels. Then fill the tank full and see if your adjustment works!

I found that if you turn the pot to the right, you will be LOWERING the resistance... which will INCREASE the current in the circuit.

And when you increase the current your LED lights will turn-off with every 5K-8K ohms you DECREASE.

Hopefully, you have enough ohm adjustment as you need to "fine tune" your holding tank sensors, but if you don't you can do the following....

PROBLEM #4

If your trim pot has no more adjustment to fix your LED problem, then you can fix this by changing just 1 resistor on the circuit board.

The resistor in question is R25 if you are talking about the Gray holding tank LED stack; and/or it's R18 if you are having trouble with your Black holding tank LED stack.

...But the next question you need to answer is this: Do you increase or lower the resistance?

Answer: That depends on your problem. Here are your two choices:

A) If too many or all of your LED lights are "ON," when your tank is empty, then you want to lower your resistance in the circuit. IE, your 10K-ohm resistor (for either R25 on the Gray stack or R18 on the Black stack) needs to be changed to a 1K-Ohm (1-Watt) resistor... and then you adjust your trim-pot accordingly to get your LED fine-tuned, , which is what I had to do to my inside circuit board.

B) If too few or none of LED lights are "ON," when your tank is 1/3 full or 2/3 full or more, then you want to increase your resistance in the circuit. IE, your 10K-ohm resistor (R25 or R18) needs to be changed from a 10K-ohm to a 18K-Ohm (1-Watt) resistor, which is what I had to do to my outside circuit board.

The goal is to make a resistor change so your trim-pot will allow you to adjust and calibrate your system so the comparator can work properly.

These are not hard modifications to make to your CB, and anyone can do it at home if you have the right resistors. ...And if you don't, then any TV repair shop near you should do it for you, and I'm guessing they will charge you $20 or less (or should).

NOTES:

On my inside CB I only had troubles with my Black holding tank LEDs, I fixed it by lowering R18 resistance from 10K-ohms to 1K-ohms.

On my outside CB I also had troubles with my Black holding tank LEDs, I fixed it by decreasing the R18 resistance from 100K-ohms to 18K-ohms.

Good luck with your diagnosis and fix!

[prathmell]

I had to replace my One Place monitor. Everything works except the Black Water fill level. How do I set it? 2011 Winnebago Siteseer

[tim myers]

I know this is an old thread, but I have been reading it off and on for the past year. I have a similar issue with my 2007 Journey, and have removed the tank level monitor board for inspection. I do have the Red (newer?) circuit board. My Grey and Black tank sensors are the no touch type that are connected to the sides of the tanks with adhesive. I have not removed the metal panels that give me access to these sensors yet.


I did not find any smoking gun with regards to cold solder connections nor did I find any broken circuit traces. I re-flowed a couple that were questionable but to be honest I do not think they are an issue.



I am actually suspecting something is amiss with the buttons I push to activate the level circuits for each tank. I have noticed that changing the pressure on the button can affect the readings of the led's. I think when I go back out to storage I will take some test leads and click to each side of the button to see if I get a more solid reading. I might get lucky and only need some contact cleaner to clean up the push buttons.



For information, my board is the red board 15130-00, and I only have one potentiometer which is the one at bottom right and I think it just works with the LP Tank Sensor.



Does anyone know of a company that is manufacturing or testing/rebuilding these boards any longer. Saw one for $965, that's not happening.



Has anyone went the See Level after market sensor route?

[JimStreit]

I was never able to find my issue. After a couple hours of investigating and testing wires in different locations, I gave up on the old panel decided to put in something new. I purchased a Garnet 709 SeeLevel II 3 Tank Monitoring System from rvupgrades.com and ran new wires for each of the sensors. For the couple hundred dollars it was a ton more accurate and took about 2 hours to get everything installed.

Good luck.

[tim myers]

Thanks for the feedback, I have been looking at the See Level system and also the Mopeka tank system.



An interesting side note is that I reinstalled my monitor board and had a good solid Empty LED on the Black, Gery and Fresh tanks when running off of battery. When I started the generator which provides power to the Converter/Charger all the levels jumped by one LED, including the Propane Sensor.


Some people are using the Mopeka wireless system for Propane, Fresh, and Grey water tanks. Mopeka does not recommend their sensor for Black tanks yet, but there is one guy on YouTube that is trying one out. Issue is that you need clear access to the bottom of your tanks not the sides, which is not always accessible.

https://www.youtube.com/watch?v=9p4MRrxTuO4