Black tank flush for two bathrooms

[Ahdmeyer]

hello, that is to fill your water tank. normal flow is for when hooked up to city water turn to fill to fill your tank here is a little u tube on it.

https://www.youtube.com/watch?v=Mgu5mKl1DRE

al meyer
3931fb
az

[RMcNeal]

Originally Posted by grass man

Hi Guys, been following your comments. I have a question, so what is the "tank fill power fresh valve for. I have the 3931 it is set to normal flow now.

Thanks

There is no gravity fill on the Montanas. This is the way you fill your fresh water tank.

[Sharko]

Originally Posted by RMcNeal

There is no gravity fill on the Montanas. This is the way you fill your fresh water tank.

I tried filling my tanks using this power fill fresh connection. Was super slow. Probably did wrong. I need a way to add water so I got an $80 water pump and pour fresh water from 6 gal. water jugs into a bucket and pump water into vent in my 3930FB.
It Was fast but can build up pressure depending on what size tubing you use.
Has anyone had luck doing it with the "power fill"?

[jmb98]

Originally Posted by grass man

Hi Guys, been following your comments. I have a question, so what is the "tank fill power fresh valve for. I have the 3931 it is set to normal flow now.

Thanks

It's for filling your fresh water tank. The switch diverts your city water to that tank. We keep a little (one dot on the monitor) in the fresh tank for flushes & sinks while we're on the road.

[ElizaBeads]

There are two flush hook ups tank flush and black tank flush 2 ..we have the Same 2020 3931 Fb ..there’s no way that they wouldn’t both be able to be flushed ..the camper would start to stink ...look beside the flush the one for the other black tank is beside it

[webbhead64]

I also have a 2020 3761FL. I believe the bottom 2 water inlets are BOTH black water flushes, 1 for each tank. I was confused at first, as the one on the right says "FILL", but during PDI was told that that "FILL" really was referring to the position of the black TANK FILL selector, normal city water flow or FILL for the fresh water tank (which redirects city water to the fresh water tank).

I have not connected to either of the Tank FLUSH inlets, but I "believe" that's what both are there for....one for each tank. Going to try it out this weekend.

[ingalmi]

So, We have a 2017 3921FB which has the master bath (including tub) and a separate 1/2 bath. The convenience center has two (2) black tank flush fittings at the very bottom of the convenience center. The forward or left fitting is for the 1/2 bath black tank flush and the right or rear fitting is for the front bath black tank. I know it’s backwards but that’s the way it really is and there are several out there exactly the same. Now for something even stranger, the 1/2 bath sink drains not into the grey tank but into the black tank. Surprise surprise! Trust me I’ve verified this 3 times. I always thought the 1/2 bath sink drained into the same grey tank as the kitchen but not so. Easy enough to verify, just turn on the sink and see which holding tank fills. You may also be surprise.

[Les Greer]

Originally Posted by ingalmi

So, We have a 2017 3921FB which has the master bath (including tub) and a separate 1/2 bath. The convenience center has two (2) black tank flush fittings at the very bottom of the convenience center. The forward or left fitting is for the 1/2 bath black tank flush and the right or rear fitting is for the front bath black tank. I know it’s backwards but that’s the way it really is and there are several out there exactly the same. Now for something even stranger, the 1/2 bath sink drains not into the grey tank but into the black tank. Surprise surprise! Trust me I’ve verified this 3 times. I always thought the 1/2 bath sink drained into the same grey tank as the kitchen but not so. Easy enough to verify, just turn on the sink and see which holding tank fills. You may also be surprise.

We have a 2019 3930FB and the left flush port flushes the front bath and the right port flushes the 1/2 bath.

[Mikelff]

Originally Posted by dfroggatt

My rig has 2 Gray and Black water Pull drains. One in main wet cabinet and second set near wheel wells.

In the Global connect panel, it registers levels in Black Tank 1, Black Tank 2, Gray Tank 1 and Gray tank 2.

What confuses me is that I do not have any specs that tell me the size of these individual tanks.

Black Tank 1 has a Spray flush valve. Black tank 2 does not. Why?

I frequently have issues in draining Black tank 1 (must be bedroom toilet).

Sure would like to know more details about these 2 black and gray tanks. Are they truly separate? What is the size of each? Hopefully someone in this forum can help me answers these questions. No manuals specify this information.

You should have this info in your owners manual? If not, get your vin number and call keystone and they can give you all the details on the build of your particular unit. The owners manual isn’t always specific either. I have seen “specs” on my model that are completely wrong, so call Keystone. That’s where I got my info. They even emailed me my factory build sheet.

[ElizaBeads]

We live in ours fulltime ...and love it ..we flush both tanks weekly

[luve2race]

To fill the fresh water holding tank.

[mbjam359]

I am glad to know the other hook up is to flush the half bath black tank. Thanks for the info.

[ElizaBeads]

Originally Posted by mbjam359

I am glad to know the other hook up is to flush the half bath black tank. Thanks for the info.

You’re welcome

[greenportbeach]

Originally Posted by Ahdmeyer

on my 3931fb i inquired at the factory and was told The second flush is the one behind the blu and red pex hoses. In my picture the one with the yellow hose end. i have put quick connects on them. The one is hard to get at
Al meyer
3931 fb

Thanks for the picture and explanation. We have the 3931FB 2020 model and are experiencing the same thing with the 1/2 bath having no way to wash it except with an external hose or buckets full of water.

[Jodybug]

We also have a 2020 3931FB. We have a bath and a half. There are two separate pulls for black tanks and two separate pulls for gray tanks. They are not in same location. One is in location with water hookups and the other is a few feet further toward the rear.

[rschaz64]

Thank you all for your valuable input!

(Man, I love this forum! :-))