Last year I called on the forum for help when I dropped the cap of my "blue stuff" down the toilet.
I managed to recover the cap, but now I have another "tank" issue.
On this trip, our gray tank suddenly read "full". We didn't think it was full since we just emptied it, but we ran water in the sink, till it was full and then drained it again.
The tank still read full, and continues to read full. We thought maybe we were tilted or something, but it stays on full.
We are guessing this is a sensor problem, and if so, what should we do about it?
Thanks in advance for all your help. We have a 2013 extended.
2012 Interstate Coach
From All Over
, More Than Anywhere Else
Join Date: Dec 2011
Posts: 10,868
I'm not an expert on the tank sensors, so I'll pawn that answer off to someone else.
But I can tell you an interim fix to make sure you don't go over-full on the gray tank:
Your Interstate's gray tank has a 26-gallon capacity. Which interestingly enough is exactly the same as your fresh water tank capacity, if you ignore the 6-gallon water heater capacity. Which you can, because you can't use the water in the water heater unless there's unheated water going into the water heater to push the heated water out. So if you're completely full with 32 gallons of fresh water, you can only use 26 gallons of it before the pump sucks air.
So in the interim until you can solve the sensor problem, don't use your municipal water hookup. Just fill the fresh tank, and draw from it for all of your water needs. Then when the fresh tank is empty, it's time to go drain your waste tanks. If you drain both gray and black every time the fresh tank runs dry, you shouldn't ever overflow either waste tank, because 26 gallons of fresh water will end up split between the 26-gallon gray tank and the 17-gallon black tank.
That's the same technique I normally use whenever I'm at a campground that only has a dump station instead of sewer hookups. That way there's almost never a need to break camp to hit the dump station at odd hours due to an over-full waste tank.
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I thought getting old would take longer!
We Just went through a similar issue. Your Grey tank sensor is located within a few inches of your grey tank dump valve. The wire connecting to it is essentially an RJ-11 telephone style connector and it's located under a rubber boot for protection from the elements. I had a bad pin on that RJ-11 that was not making a connection and the gauge showed full all of the time. To expose the connector you may have to cut a cable tie holding on the boot and pull back the boot to expose the connector, unplug the connector and inspect the pins for corrosion and dirt or water damage. If you do not see any damage try spraying the receptacle with WD40 and do the same with the connector then brush with an old toothbrush and reinsert the connector into the receptacle. Try the gauge now. Does it work?
If you have a bad pin like I did, you will have to cut off that connector and crimp on a new one. It's not hard to do with the correct tools but make certain you get the wires lined up in the right direction.
Hopefully you get it working.
Now make sure that boot is pulled back up and the cable tie put back in place to keep out the water and crud.
Good luck,
Kevin
Ps... after writing all that I looked up what you owned (wasn't sure what a 2013 extended was) so my instructions may or may not be any help at all. Lol.
It worked for me on my 2011 FC28 with Catcon sensors. Sometimes when I use the iPhone app it's tough to see immediately what forum a post has been made in. [emoji15]
According to 'Wheeling it" website; (see link below);
"The GEO method is a home-made cleaning technique that’s been around in the RV community since (at least) the early 80’s."
"To understand why tank sensors go bad it’s worth understanding a little about how they work. Most RV tank sensors are basically just 4 screw probes that stick into the tank. When liquid hits the screw it makes contact & completes a circuit that turns the LED light on your panel on."
"Over time crud and slime covers the screws causing connectivity when there really is none (so sensors “think” the tank is full even if it’s not). It’s a really poor system, but it’s a cheap one which is why it’s so widely used. So, the key to making these things work again is simply to clean off that grime."
"Most RVers use just 2 common items, both of which you can get at any big department store:
1. Calgon Water Softener - This stuff helps to break down water surface tension, clean scum and prevent hard mineral deposits. I’ve used Borax on occasion when I can’t find Calgon and find it works just as well.
2. Dawn Dishwasher Detergent - The “original formula” blue detergent is excellent at cutting grime. Laundry detergent works too.
After you dump pour 1 cup of Calgon and 1 cup detergent into the tanks. Leave them in until your next dump. Before driving some RVers will also throw a bag of ice-cubes down the tank to “scour” their walls (we’ve never done this, but others swear by it).
And that’s really it! We don’t use the GEO method each time we dump, but just whenever our sensors need an extra cleaning. Either way it’s a simple, easy and environmentally-friendly method to keep sensors mostly clean."
2012 Interstate Coach
From All Over
, More Than Anywhere Else
Join Date: Dec 2011
Posts: 10,868
Quote:
Originally Posted by Mister B
"The GEO method is a home-made cleaning technique that’s been around in the RV community since (at least) the early 80’s."
This has appeared on AirForums before. As with everything else that ever appears on AirForums, reception varied from wholesale endorsement as the best thing since sewer hookups to wholesale condemnation as being just one step up from voodoo. I personally fall somewhere in the middle of the acceptance/rejection spectrum.
Strictly speaking, you don't need both dishwashing liquid and water softener UNLESS the water you use is so hard that it leaves behind white crusty calcium deposits (like in SW Oklahoma where my kid brother lives). For most people, dishwashing liquid alone works just fine, by reducing the surface tension of water so that it soaks into cracks and crevices to small for a drop of water to otherwise enter.
Rather than using ice to scour the tank (which may work on potholed Louisiana highways but not many other places where you don't get a lot of sloshing to move the ice around), I add HOT water to the black tank. Hot water softens solid wastes, which allows my macerator pump to chew through it better. The last thing I would want is un-melted ice jamming my macerator pump.
Not widely known, one problem with tank sensors getting gummed up is the use of RV antifreeze in tanks previously treated with some brands of tank treatment. They chemically combine to form a substance technically known as "goop." Best defense against this is, when you winterize, thoroughly rinse the waste tanks to get rid of tank treatment residue before adding antifreeze. And when un-winterizing, thoroughly rinse the waste tanks to get rid of antifreeze residue before adding any tank treatment.
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I thought getting old would take longer!
Your Interstate's gray tank has a 26-gallon capacity. Which interestingly enough is exactly the same as your fresh water tank capacity, if you ignore the 6-gallon water heater capacity. Which you can, because you can't use the water in the water heater unless there's unheated water going into the water heater to push the heated water out. So if you're completely full with 32 gallons of fresh water, you can only use 26 gallons of it before the pump sucks air.
Never underestimate the "Beer Factor"
A 30 pack is almost 3 gallons
From the 'Beer Factor', I assume that you meant that the 30 pack of beer would be added gradually to the black tank after filtering it, & not as a primary treatment for the tank sensors added directly from the cans!
2012 Interstate Coach
From All Over
, More Than Anywhere Else
Join Date: Dec 2011
Posts: 10,868
Quote:
Originally Posted by WayneG
Never underestimate the "Beer Factor"
A 30 pack is almost 3 gallons
But recycled beer ends up in the black tank, and you still won't overflow the gray tank. I mention this only because the thread was about gray tank sensors before thread drift struck again.
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I thought getting old would take longer!
... Ps... after writing all that I looked up what you owned (wasn't sure what a 2013 extended was) so my instructions may or may not be any help at all. Lol.
It worked for me on my 2011 FC28 with Catcon sensors. Sometimes when I use the iPhone app it's tough to see immediately what forum a post has been made in. [emoji15]
OP - lamato has a 2013 Interstate Lounge Extended model. It is a Class-B motorhome built on a 24 foot extended length Mercedes Sprinter van.
I realize you were just trying to be helpful but the Interstates have a completely different system with no RJ-11 connectors.
I'm having a similar problem with my 2013 Interstate's grey water tank sensors. I have used dishwasher soap before and it did seem to help - need to do it again.
The sensors are glued to outside of the plastic tank. I think they are some sort of capacitive driven sensors. I think I can find some technical info on them and will post later. But a build up of crud on inside tank walls probably messes with the sensors. Unfortunately you can't get inside the grey water tank to do any cleaning, much less add ice cubes to the tank. The ice cube method is for black water tanks that let you dump ice cubes down the toilet.
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- - Mike
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2024 Airstream Interstate 19e AWD
Previous: 2013 Airstream Interstate 3500 Ext Lounge
2012 Interstate Coach
From All Over
, More Than Anywhere Else
Join Date: Dec 2011
Posts: 10,868
Quote:
Originally Posted by Boxster1971
Unfortunately you can't get inside the grey water tank to do any cleaning, much less add ice cubes to the tank. The ice cube method is for black water tanks that let you dump ice cubes down the toilet.
Good point. I lost track of that my own self. A gray tank should already have dishwashing soap in it, so the tank cleaning process of the past few posts isn't applicable.
By the way, if I'm not using disposable paper plates, and there's any food residue on the dishes, I use the handheld shower head in the wet bath and rinse the dishes into the toilet, so the food residue ends up in the black tank rather than the gray tank (the dishes never enter the toilet, they're just held above the toilet while being rinsed).
My point about accidentally mixing RV antifreeze with tank treatment chemicals to create a sticky slime is still applicable to both black and gray tanks, though.
__________________
I thought getting old would take longer!
Good point. I lost track of that my own self. A gray tank should already have dishwashing soap in it, so the tank cleaning process of the past few posts isn't applicable.
By the way, if I'm not using disposable paper plates, and there's any food residue on the dishes, I use the handheld shower head in the wet bath and rinse the dishes into the toilet, so the food residue ends up in the black tank rather than the gray tank (the dishes never enter the toilet, they're just held above the toilet while being rinsed).
My point about accidentally mixing RV antifreeze with tank treatment chemicals to create a sticky slime is still applicable to both black and gray tanks, though.
Good tips Protag. I should have been clearer - you want to use automatic dishwasher soap. It doesn't foam up like regular dishwashing soap.
__________________
- - Mike
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2024 Airstream Interstate 19e AWD
Previous: 2013 Airstream Interstate 3500 Ext Lounge
OK – dug up some information on the Tank Monitor system on Interstates. It looks like a custom version of the TouchSensor LevelGuard SensaTank RV100 Multi-Tank Monitoring System.
Attaching a page from 2015 Interstate owner’s manual that has a basic description of the system.
Also attaching the SensaTank RV100 installation instructions that provide a bit of technical detail. The Airstream version is slightly different since the sensor interface electronic module is built into the display as shown in the photo below of the back side of the Monitor Panel taken a few years ago when my system stopped working. I got a new panel from the dealer under warranty.
If you really want to geek out I’m attaching a whitepaper from LevelGuard on the field-effect sensors. RV tanks sensors are not their only use since LevelGuard makes and sells mostly sump and sewage pump switches using the same sensors.
“Does LevelGuard sense through scum and scale buildup?
Our pump controls were tested and approved for the application by both Underwriters Laboratory (UL) and a third party testing lab. Both LevelGuard models have been tested to sense through up to a 1/8” of mineral buildup.”
But that answer was for their sump pump controls submerged in water. Our water tank sensors also go through the plastic tank wall. Bottom line: scum build up inside our tanks is likely the main cause of erroneous readings.
__________________
- - Mike
--------------------------
2024 Airstream Interstate 19e AWD
Previous: 2013 Airstream Interstate 3500 Ext Lounge
But recycled beer ends up in the black tank, and you still won't overflow the gray tank. I mention this only because the thread was about gray tank sensors before thread drift struck again.
Sorry, I have black tank problems on the brain. We just got back from 10 days in the woods at a festival with some luxuries such as water and electric.
Our gray tank filling is not a problem since I use a drain hose into a crushed rock dry well. The black tank needs to be pumped when the porto potty guys come through.
My sensors readout is the 4 light type E-1/4-1/2-3/4-F The black tank was reading 1/2 for a long time so I thought our usage was minimal. Then bam it was reading F, the 3/4 light never came on! Fortunately the porto truck emptied us the next day, but that left me with a bad readout.
My readout display is shared between all tanks with parallel wiring and the rest work fine. Either my sensor is covered with something preventing contact with the liquid or the wire to only that sensor contact is broken.
As for reaching the grey tank for the ice cube method, if your vent pipe is strait down, drop them in there one at a time.
I saw a video test of the icecube in the tank. here it is and for waht it's worth:
Do Ice Cubes in the RV Black Tank Really Work? - YouTube
Video for putting ice in rv black water tank▶ 8:03
...Your Interstate's gray tank has a 26-gallon capacity. ... don't use your municipal water hookup. Just fill the fresh tank, and draw from it for all of your water needs. Then when the fresh tank is empty, it's time to go drain your waste tanks. If you drain both gray and black every time the fresh tank runs dry, you shouldn't ever overflow either waste tank
Great strategy, and thanks for the reminder that the available fresh (minus the hot) is about the same as the gray. Our gray indicator regularly goes to 2/3 when the fresh is still at 2/3, so obviously one or the other is not well calibrated.
But there may be different results if you aren't almost perfectly level. We recently did a test, first emptying both black and gray, then filling fresh to the brim. Using only the pump, not hooked to city water, we drained the fresh by running cold water into the galley sink. We timed, and observed the indicator lights. After about 25 minutes, the gray water light went to red. at 28 minutes, the sink stopped draining. There was still water left in the fresh, though its indicator was red also.
The test was not ideal because the nose of the van was pitched down a bit. Not severely, but enough to be noticeably off level. I want to repeat the test sometime where are perfectly level.
Much has been written about tank sensors and inaccurate readings. Briefly, the sensors are relatively short strips glued to the outside of the tanks. Since they are not exactly the height of the tank and the tank is not always level, inaccurate readings are likely. The strips can be mounted to read either 100% full or 100% empty. The accuracy is reduced when there is accumulation of stuff on the inside walls of tanks. Mineral deposits, crud and stuff inhibit the accuracy.
Recently, we had the tanks cleaned with a high pressure, power washer type wand inserted into each tank, swirled around for a while and released all sorts of clinging matter. All good now so don’t blame your sensor.
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