Does newer 3921FB have black tank flushes?

[astrungis]

Does anyone happen to know if the newer 3921FB has black tank flushes on both toilets? I presently have a 2013 and ordered a 2019. The 2013 had only one flush on the master bath but not the half-bath downstairs. I had to install one downstairs. An obvious design error that I hope was corrected since 2013. Thanks in advance.

[Mikendebbie]

Yes - there are separate connections for the front black tank and rear black tank flush systems. I could not find a good pic with a straight on view (sorry) - but the pic below shows basically where they are.

[Wicked1]

Most newer units have them since I have owned RV’s in 2012 had them on all mine.

Most mid to high end will always have them and some of the lower end models do but not all low end units do, all Montana’s will have them

[hardinrob]

I have a 2018.5 Montana 3921FB and mine does have black tank flush on both black tanks.

[Mikendebbie]

I have noticed that the rear black tank (serving the half bath) gravity drains and flushes quickly and thoroughly. The front tank not so much. The rear tank empties in more of a “gush” (good gravity flow). The rear tank is more like a slow trickle...better than a trickle but it is definitely not a gush. Even if I close the valve and let it fill - it never comes out in a gravity gush like every other black tank I have ever had. Yesterday when we were getting ready to leave I used the swizzle stick to try to clean it out really good then back-flushed it several times. I think I may try to run an old hose up the pipe to see if it loosens something up better. I have a feeling it is due to the drain pipe configuration but I have not tried to trace the piping. If the “trickle” is just the way it is - I’ll just deal with it.

I’m just curious if other 3921FB/3920FB/3931FB owners have noticed the same thing!

[martyperu]

We have s 2018 3920FB. I was confused on black flush issue also. Dealer stated on one tank flush.
I contacted Keystone rep and after some back and forth emails and pictures there is indeed flushes for both tanks. They are the lower water hookups in convenience center. On mine front one flushes back tank.Back one fushes front tank. Go figure.

[TracyD]

I have a 2017 3920FB. it's flush connections are located just like yours.

Originally Posted by martyperu

We have s 2018 3920FB. I was confused on black flush issue also. Dealer stated on one tank flush.
I contacted Keystone rep and after some back and forth emails and pictures there is indeed flushes for both tanks. They are the lower water hookups in convenience center. On mine front one flushes back tank.Back one fushes front tank. Go figure.