34F Adventurer 2025 brand new issue with the toilet sensor and black tanks.

[gwillcox]

We took our brand new Adventurer out for the first time and after 2 flushes of the toilet the red indicator light came on indicating the tank was full. We attempted to empty the black tank but almost nothing came out and it was clear water. We have 2 black tanks for some reason one on each side of the motorhome and a macerator, but only one bathroom. Last night the only way anything would come out of the black tanks was with both of the black tanks open and pushing the macerator button but even the macerator would stop after a minute and then nothing would come out of the black hose, and the macerator button had to be held the whole time it was working
Inside the Home Screen said it was 60% full. We got it down to 20% full but the toilet is still showing yellow on the light indicating it is more than halfway full. Any ideas what is going on?

 

[Morich]

First stop may be to verify which you might have as parts drawings show a 34W or a 35F? But it appears to fit for the 35 F?
That RV does show a black tank under both bath stools and that may be a clue, depending on which tank you were wanting to drain?
Seems to be a bit awkward as you do have two tanks and one requires pulling a different valve to open it to the pump.
We have a really great tool to study where and what we have on newer RV:
Interactive parts drawings here:

Parts Catalog

Going to plumbing and waste we can get a look at what they have given you and spot some ideas of what might be going on!

This looks like a guess on what you find? Do verify before trusting !
First most will want to dump the black tanks, no difference on which of those goes first? Many like to save the grey water to help flush the hose after the big stuff is drained.
I might first drain the main black tank that is shown in purple by pulling that valve?
Next I might have first and second move backwards depending on where the maceator pump switch? I would want the pump to get ALL the waste brfore runnng it too long as it may help to "lube' the impeller? But the main idea is that it has to have BOTH the valve at the main as well as the second one at the second tank BOTH open to get the real volume of waste out! If only getting a small amount of water out, I might guess that is only what has leaked past the valve at the pump??
But with BOTH open and then turn on the pump, it should drain the total black!
Then as final I go for the grey to help flush the hose a bit!
Welcome to all the tricks they hide on NEW RV???

I like pictures better than written anyway but sometimes it takes even more than that!
Wish you luck?