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Old 01-20-2016, 09:26 AM   #1
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Tank Monitor Expectations?

Should I expect the tank gauges to work properly? I have a Sesimic 4212 with 2 greys and 2 black tanks plus 146 gal fresh (potable). None of the tanks read properly, we boondock constantly. Yesterday fresh tank said empty and filled with my 45 gal tank on the pickup. Gauge went from empty to full with on 45 gal tank. Camping world looked at it in October and said AOk?

Rear black tank is stuck on 2/3 full when empty. Have flushed and flushed the tank 8 times with black flush system?

Before anyone chimes in about single ply TP, don't we use it always.

I am still under warranty

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Old 01-20-2016, 02:24 PM   #2
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I have never relied on the black or grey tank indicators because they are not accurate after they become fouled by debris which is most of the time. The fresh water indicator has worked fairly well over the years but sometimes says 2/3 when it is full.


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Old 01-20-2016, 02:29 PM   #3
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FW tank usually works fairly decently. Once in a while mine does not. If you can check the sensor wire connections. When new I used liquid electrical tape, to help eliminate potential corrosion issues.

The other tanks always are untrustworthy, you can buy better sensors, that are more reliable. The black tank has issues with TP hanging up on the sensors and giving you a false reading. Make sure to have lots of water in the tank when you dump. After dumping, add water to the tank, on a your unit, maybe 5 to 10 gallons. This will slosh while driving. The Grey tank seems to have issues with grease on the sensors. When ether tank starts to give me issues I put about a cup of liquid fabric softener in the tanks with lots of water. So the tanks slosh while driving. For me two trips back to back my sensors are working again. I still do not always trust them.
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Old 01-20-2016, 02:30 PM   #4
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Ditto. The tanks sensors used by most manufacturers are the bare minimum grade. There are many better that can be purchased and added if you want but don't expect any degree of accuracy from what you have.

Many people spend a large part of their lives obsessing about the tank levels. me, I just mentally keep up with it. I admit, it's harder with small kids and when you are boon docking.
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Old 01-20-2016, 02:46 PM   #5
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For the most part they are worthless. Black tank look down the whole with a flash lite. Grey is a matter of judgement. After a couple days usage, drain into a tote and record the gallons. Will allow you to figure when you're needing to dump. Fresh water I fill whenever I get a chance and keep a 6 gal water can if I run out.
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Old 01-20-2016, 05:05 PM   #6
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Tank Monitor's

You talking bout those Lie-O-Meters????? You can expect them to lie!!!
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Old 01-20-2016, 08:37 PM   #7
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I'm pretty good about keeping my tanks clean. I use PLENTY of water, fill and flush during breakdown using the tank flush. I just emptied my tank to winterize my trailer and the tank read 1/3 full after I emptied it. It read full before that, but I only drained maybe 10 gallons out. So no, the black tank monitor is not to be trusted. For me, grey and fresh have been relatively good, but not great. If you want it exact, drop some coin on some higher end sensors, otherwise you're left to make educated guesses and rely on experience like most of the rest of us.

Ive thought about doing that myself, but so far it hasn't really been a problem, so I'm using those funds for other stuff.

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Old 01-21-2016, 08:21 AM   #8
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My tank monitors work this way... I look down the toilet to see how full that tank is and when water starts to accumulate on the shower floor I know to dump the gray
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Old 01-21-2016, 08:59 AM   #9
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My black tank '1/3' light is always on... but I always add water after dumping & flushing so that is OK by me.

Several times this year we boondocked for 4 days without problems. Our rule of thumb for our tanks and the way the two of us use water... dump every 4/5 days.

We did go 5 full days once, I looked down the toilet, but didn't see anything. But like Seann said, the water stopped going down the shower drain the morning of day 6.
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Old 01-21-2016, 11:02 AM   #10
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Same here with my new Seneca. I talked to my service man about the problem. He just raised his eye brows, and sighed. Their is no fix to the problem. I understand some company makes a system that attaches to the outside of the tank that will monitor the fluids. Does anyone have this system, and how does it work. Is it difficult to install. Why doesn't Jayco use this system?

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