Do I use the macerator button for gray tank empty?

[mrlynch1953]

On the new (to me) Class B, the macerating toilet chews up everything; and then when I open the valve and push the button the black tank is pumped out. My gray tank has a different valve and seems to be a good gravity drain. Is there a reason I should push that button for the macerating toilet/pump when I drain the gray tank?

[YC1]

Cannot exactly visualize your setup but if they both come out the same drain versus separate then yes run the macerator. It will be much quicker.


Some macerators have a gray water bypass. That is, you can leave the gray tank valve open and the gray water will slowly drain. This is handy when you have hookups and use the shower a lot etc. But before dumping the black tank it is best to hold back the gray so you can clean the lines with it.

[Rocinante440]

As I read your posts, I'm entirely unclear whether you have one macerator (e.g. one in the toilet itself or one in the black tank drain line), or maybe have two macerators (e.g. one in the toilet and one in the black tank drain line). If you clarified this, it would probably help us all help you.

[mrlynch1953]

Originally Posted by YC1

Cannot exactly visualize your setup but if they both come out the same drain versus separate then yes run the macerator. It will be much quicker.


Some macerators have a gray water bypass. That is, you can leave the gray tank valve open and the gray water will slowly drain. This is handy when you have hookups and use the shower a lot etc. But before dumping the black tank it is best to hold back the gray so you can clean the lines with it.

My valves for gray and black are separate. Gray is near the drivers seat/door and black at the rear. Gray drains well via gravity. With my other RVs i started dumping a full gray after a full black but now i leave gray open and fill black twice with fresh water and dump twice to rinse out the hose. I can’t figure out how to fill this macerating toilet/black tank. So i fill the bowl with my hose and flush a few times, then push the button to expell from the black tank again but still not clear water which is what i would like to see. Then i rinse the hose well with water after removing it. If i put in a Y connector i could do thisdifferently.