Black & Gray Tank Gauges

[gfidk]

Just returned from our first 3 night camp trip with our 2021 CC388DB and am already noticing tank gauge capacity discrepancies which lead to several Qs:

I had thought I had only 3 tanks (fresh/gray/black) but have 5 gauges on the panel (with double grays/double blacks). Should these "duplicates" raise in parallel (suggesting a common fill line) or is one an overfill (suggesting the 2nd tank fills once the first is full)?

Or, are these "dedicated" holding tanks (one black for each of the two toilets)?

Or, maybe I really do have only 3 tanks but have double sensors on each for greater accuracy?

After dumping, one black gauge still shows partially full. Now that I'm home, I'm going to immediately add about 3 gal water/dawn dish soap mixtures to each toilet to assure tank(s) sensors don't dry out (from other forum tips).

[camaro80]

I looked at your floor plan, and see that you have two washrooms. It is possible you have two black and two gray tanks, as that's how I'm set up on my 2011 35K with a bunkroom washroom, so five tanks including a galley tank. And to keep the sensors clean I just do a good long rinse until the water is coming out mostly clear.

[Thomas ho]

they are usually wrong ,they get something on them . i use my spydy senses to dump when i think they are almost full

[NJKris]

They frequently show false positive readings, but should never show false negative readings. They also will change when you come back later and check, as the sensors dry out in an empty tank.

[SimchaSabre]

And Calling what we have to measure tanks levels "Gauges"is a bit over optimistic. At best, there's indicators. Over time you will gain a sense on how to use them to help you understand your level status. For example, we use sound and pitch change to know our black tank level.

[gfidk]

Originally Posted by camaro80

I looked at your floor plan, and see that you have two washrooms. It is possible you have two black and two gray tanks, as that's how I'm set up on my 2011 35K with a bunkroom washroom, so five tanks including a galley tank. And to keep the sensors clean I just do a good long rinse until the water is coming out mostly clear.

Many thanks for the feedback - Since my grays both seemingly gauge in parallel (and they're not as "critical" as are the black tank levels), might they be bridged? Do yours rise independently?

Also, do you know if yours is running two separate black flush lines - if we have separate black tanks? Seems this would be needed.