Black Tank Flush

[krobb]

Hello All, I’ve got a question that I can’t seem to find the right answer to reading these posts. I am the proud owner of a 2021, 3931FB. It is a bath and a half unit. My outside water hookup center, only has (1) black tank flush connection. I have seen other posts stating they have (2) connections. I asking my fellow 3931 owners if you have 1 or 2 black tank flush connections in your hookup center? If I am supposed to have two, then it looks like it might be a warranty issue. Thanks!

[RickyRobert]

Second set of tank pulls are in their own compartment just to the right of the 50-amp cord winder. No lock involved. The two pulls take care of the second black and grey tanks. Careful when reaching in - mine has a number of pointed screw ends sticking out (suggest that you wrap them in something, even slightly oversized drywall plugs). You can monitor their "fullness" from the app or the inside control panel.

[krobb]

I’ve got the the location of the valves. I’m wanting to know about the “Black Tank Flush”.

[RickyRobert]

Sorry about that ... My second flush connection is in the water hook-up center. Going to do my weekly check on the unit this afternoon; can attach a picture later today.

[krobb]

Thanks RickyRobert. I’m taking it that you have a 3931 FB as well. If so, I think I’ll have a difficult time running the flush line. I’ll be waiting for your pictures.

[Ahdmeyer]

the other wash connection is right across from the one that is marked tank wash to the right, kind of hidden if u see the tank fill power fresh knob below that knob you will see the word fill it is right next to the world fill. i have a picture of mine i have added quick disconnects on mine as you can see also a hose extension for the one clean outlet otherwise hard to screw a hose to. the one above the left tank clean out is marked city water connection, be sure when fill the fresh water tank you do not hook up to the clean out or you could have areal mess if you hook up to the wrong one. hope this helps
al meyer
3931fb
az

[krobb]

Thanks Al. I wasn’t sure if this was a flush connector or not. Is it the flush for the 1/2 bath? That what I’m assuming!

Thanks again and how do the quick connects work for you?

[Ahdmeyer]

quick connects work great. i believe the right one is for the half bath yes again dont know your background with rving but make sure the black is opened when flushing. i sometime close it for a bit and let it fill just to get more wash pressure but am careful not to forget it or the black could over flow inside.

almeyer
3931fb
az

[RickyRobert]

Here's a confirming picture from my unit - same configuration. I use an elbow connector in order not to stress the connection or the existing piping, but I like the idea of just leaving quick connects behind. This tank flush is for the half bath black water tank. While you are exploring all of the unmarked "stuff" on your rig, did they label all of the extra 12V switches in the staircase panel? If not, I can send you a picture of mine all labeled after the fact.

[Mikendebbie]

krobb - I have similar unit (2018 model). My rear black tank flushes like a champ, but I have to work longer on the front bath black tank. The reason is in how the tanks sit in the frame. If you look at the screen shot below - the rear/half bath black tank sits in the higher section of the frame (B). The front bath tank is located in the lower section (A)...so, the half bath tank has the advantage of higher elevation to help it flush and rinse it out. The front bath tank takes more time and “fill then flush” cycles for me.

[Ahdmeyer]

minor details, how come they cannot or do not label the one flush tank, i had to ask while on a tour at keystone about where the other flush was . guess i should have asked then why it was not labeled then,lol
al meyer
3931fb
az

[krobb]

All good now folks. You answered my question, as I was expecting. Yes, I’ve been RVing for many of years and now finally going to enjoy this 5er I hope! Thanks again everyone!