water inlet

[hrtelkrobert]

just bought a 2015 elkridge 37 ultimate, after getting home and washing it, i noticed that there is another water inlet connection near the rear bathroom door. Is this a black tank wash out for the rear rest room. and if there is another tank how many gallons is that one. my PDI was the worse i have ever had!!!
thanks

 

[BigJim45]

Looks like you have this setup so I would say yes it's a black tank wash

Gray Tank 120 gal=3 gray tanks
Black Tank 80 gal=2 black tanks

 

[Dodge06]

Yes that is a flush for the black tank it is same set up as my 2015 37 qb silverado

 

[GMCaddic]

It also should have a sticker by it saying open tank valve before putting water pressure to it, or something like that mine does.