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Old 06-03-2013, 06:52 PM   #1
Join Date: Feb 2013
Location: Southern Indiana
Posts: 32
Tank level guages

Anyone out there have an answer for incorrect holding tank levels on the control panel? The grey and black water tanks are both giving false readings. I can completely empty them both, and they will still show at least 1/3 full. Sometimes 2/3 full. I can flush out the black water tank and sometimes it will go as low as 1/3 still full, but never any lower. They were both showing empty when we took our RV down to our leased lot and set it up. Seems like they have never worked right since then. The regular water tank shows correctly. I have twice last weekend drained the black water tank into the 27 gallon portable holding tank we have to haul to the dump station. Both times the reading was 2/3 full. After emptying twice, the 27 gallon portable tank is only about 2/3 full. We keep the chemicals in the tank as directed. Any ideas?

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Old 06-03-2013, 07:01 PM   #2
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The tank gauges are notorious for being wrong. Some people swap then out with Horst Miracle Probes (if you search the forum for this- Herk did some posts on their installation).

I find that to have accurate readings, I have to *flush* my black tank after dumping it. But, I also have sewer hookups and am not hoofing the black water via totes. I usually run the flush 3 times with 6 minutes of water and dump after each re-filling.

Though, I've personally have never had issues with the gray. But the same Herk mentioned above has.

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Old 06-03-2013, 07:10 PM   #3
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My indices do not read empty until sometime after emptied. I believe it's due to residual moisture in what ever tank this happens. Eventually though the indicator does show empty.
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Old 06-03-2013, 07:36 PM   #4
Join Date: Feb 2013
Location: Southern Indiana
Posts: 32
Tank Level Gauges

I have noticed that they will sometimes drop to the next lower level after a period of time. But since both the gray and black tanks are used regularly when we are staying in it, it does not really have time to stay completely empty long enough to tell if it would go all the way back to empty. I always empty both tanks before leaving on Sunday. We will leave the gray tank completely empty, with it still showing either 1/3 or 2/3 still full. The black tank I will empty, and then only run a gallon or so of water into the tank so that I can add the chemicals. Upon returning the next Fri., neither one will be showing empty. They will still be either 1/3 or 2/3 full on the gauge. Even though I know they are neither one near the levels they are showing, I hate to just ignore the readings because of the big IF
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Old 06-03-2013, 07:55 PM   #5
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There is another alternative to those "miracles". You should consider capacitive tank-level sensing. See this: or this: NUWA is/was using the second of these and I was very impressed. The first is available from Camping World.
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Old 06-03-2013, 08:09 PM   #6
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After you've camped with it for a while, you'll soon figure out the number of days under normal usage before the tanks are full. It's easy to verify the level in the black tank by looking down the toilet with a flashlight as it empties directly into the tank. The gray tank when full will have standing water in the shower base.

If you search the forum for GEO Method, it will keep the tanks cleaner and the sensors reading more arrucately.



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