Anyone know what this thing under the trailer is?

Homebodyatheart

Dmerzbac, mine (ok, ours...) is coming in a month sooner than planned, but our T@bitat isn't ready for occupancy yet so the dealer will store it till we are ready for her. I do get visitation rights (I asked), just can't driveway camp yet! Sigh...

ScottG

JimEngel said:

Also, assuming water can flow backwards through an unpowered pump, it looks like water from the city water connection would just fill up the tank and flow out through the fresh water filler/vent.
We have not used the city water as a water source, do those people who do find it also automatically fills up the tank?

Nope. Much in the same way that running the pump doesn't send water shooting out the city water connector, hooking up to city water does not fill the fresh water tank.

Good points, though--gotta be another check valve somewhere down in those nether regions behind the bathroom wall...

ScottG

Photomom said:

dmerzbac said:

Thank you, ScottG! (and Photomom)

Yeah, that looks like my rat's nest all right. 

I still maintain that's a great photo. Study it with your new schematic in hand and that "rat's nest" will suddenly start to make perfect sense!  :-)

Sharon_is_SAM

JimEngel, the city water connection runs separate from the fresh water tank system.  Connecting to the city water outlet will not fill the tank.  Only way to fill the tank is via the external pour spout.  Also, the ScottG diagram above shows flow direction.

Sharon

SweetlyHome

Apparently there is a check valve in the city water fill fitting.  This keeps the water from the pump from going that way.  Pretty sure this is true as our check valve has likely failed.  If we don't cap the city water fill and run the pump using the storage tank for a water source water shoots out of the city water fill.  

ScottG

SweetlyHome said:

Apparently there is a check valve in the city water fill fitting.  This keeps the water from the pump from going that way.  Pretty sure this is true as our check valve has likely failed.  If we don't cap the city water fill and run the pump using the storage tank for a water source water shoots out of the city water fill.  

It's pretty hard to see down there, but if I reach in I can feel something right behind the fill port that resembles a check valve. Even trickier would be getting to it for replacement--one of the first questions I asked on this board was "How do you access all the plumbing buried behind the bathroom wall?" As you can probably deduce--there's no good answer. You might be able to remove the port and valve from the outside, but I haven't inspected it closely enough to say that with any confidence. If you ever attempt to fix it, let us know what you discover!

ChanW

Nope, the city water connection doesn't ever fill the fresh water tank.

There is (ie: must be) a check valve between the fresh water tank and the general system. I thought it was incorporated into the pump.

There's also a check valve on the city water inlet, to keep the water from blowing out there when using the pump.

I'm thinking reindeer skivvies are "seasonally correct", today.

JimEngel said:

Also, assuming water can flow backwards through an unpowered pump, it looks like water from the city water connection would just fill up the tank and flow out through the fresh water filler/vent.
We have not used the city water as a water source, do those people who do find it also automatically fills up the tank?

SweetlyHome

We have a 2012 "L".  I have discovered that the middle cabinet shelf over the tank comes off.  Obviously designed that way.  I took these pictures with cellphone by holding it freehand.  In my opinion only a small child could actually reach in there and do anything.

Leaves me wondering how one would replace the city water connection as it is hard piped in.  I would be afraid of twisting or pulling on it from outside would break the pipe.  Has anyone tried this replacement? 
 

ScottG

Took another look and confirmed there is no separate check valve between the pump and the distribution lines. I agree with ChanW that it must be incorporated into the pump itself--probably involving the "patented unique diaphragm design" touted in the pump literature.

ScottG

SweetlyHome said:

We have a 2012 "L".  I have discovered that the middle cabinet shelf over the tank comes off.  Obviously designed that way.  I took these pictures with cellphone by holding it freehand.  In my opinion only a small child could actually reach in there and do anything.

Leaves me wondering how one would replace the city water connection as it is hard piped in.  I would be afraid of twisting or pulling on it from outside would break the pipe.  Has anyone tried this replacement? 

Wow! That opening looks like a garage door compared to the tiny mouse hole provided in the S model.  :-)

I agree with you the rigid piping would make it hard to extract the city water connection from the outside. Somewhere prior to 2015 the switch was made to more flexible PEX tubing, possibly (depending on several other factors) allowing enough slack/give to pull the whole assembly out far enough to replace it.

It's hard to see from your photo, but I'm not sure there even is a check valve on the city water connection--maybe the original 2012 design called for simply capping the port when not in use? In any case, your cap method sounds a whole lot easier than trying to replace/install a new valve--so long as that is working, I'd be inclined forget about it and camp on!