lavatory drain in International Signature 30rbq

[diabu]

We are considering the installation of a composting toilet in our new pre-owned 2019 International Signature 30RBQ. In looking through the owner's manual, it shows the lavatory sink draining into the black water tank. Is this correct? If so, is it possible to re-route the sink water to the gray tank without much trouble or is it easier to just keep the black tank and drain the lav water from there?

[Cyclist]

We have a 2012 28 ft. and the sink in the lavatory definitely does drain into the black water tank.

[Coloradobus]

Talk about a lazy design. Geeze!, can airstream make em any cheaper and raise the price tag. Now i could see grey water being pumped from grey tank into toilet us, then flushed to black tank. But to purposely fill black tank with grey water. .?? Wonder where the shower drains into. Cripe

[mythbuster88]

Originally Posted by diabu

We are considering the installation of a composting toilet in our new pre-owned 2019 International Signature 30RBQ. In looking through the owner's manual, it shows the lavatory sink draining into the black water tank. Is this correct? If so, is it possible to re-route the sink water to the gray tank without much trouble or is it easier to just keep the black tank and drain the lav water from there?

You are right. And since the composting can does not use the black tank let the bathroom sink use it.