Airstream Forums

Airstream Forums (
-   Classic Motorhomes (
-   -   Mystery pluming leak (

tevake 02-18-2015 10:48 AM

Mystery pluming leak
For some time now I have been getting a damp spot between the shower and the head occasionally after taking a shower.
I've checked both the plumbing going up the closet wall to the shower,me and the drain under the shower. Both seem fine.
The damp spots are in the middle of the hall between the shower and the head and just in the head door at the foot of the structure under the toilet.

So my question is where does the supply line run from the head to the shower?
Before I tear out the carpet or drop the grey water tank I wanted to ask here about the routing for the water line from the head to the shower.
There does seem to,be a slight dip in the floor in the area crossing the hall.
Is there a channel in the floor for the pipe to cross over? If is under the floor then why would the carpet get damp?

Can anyone shed some light on this for me?

Cheers Richard

tevake 02-18-2015 10:53 AM

1 Attachment(s)
Here is a pic of the damp area.
Lot two previous posts trying to add a pic.
Now the pic comes out upside down:angry:

Thanks for any help

AnnArborBob 02-18-2015 11:35 AM

I can't answer your question about the exact location of the water lines but I can say that they are below the sub-floor. Unless your trailer is also upside down (:lol:) I don't see how a leak under the sub-floor would show up on the carpet like that. We had water on the floor outside our shower in the past and found out that the shower door's seal on the bottom had fallen off and water was getting out of the shower stall there when in use. Airstream replaced the seal and put in a small block under the door to keep it from sagging and that seemed to solve our problem.

It turns out that the leaky shower door situation is quire common on Airstreams. You might want to use the search function for "leaky shower door" to see if you can find a thread that describes that repair.

Best of luck.

dadstoy 02-18-2015 12:01 PM

4 Attachment(s)
Hi Richard,

Let me just throw this out as a possibility. You mentioned the leak occurs after using the shower. I had a similar leak a while back. I checked all the plumbing without the shower running and couldn't find the leak.

Finally I found the leak. It was a cracked pipe on the output side of the shower valve, so it only leaked when the shower was running. It was a bear to fix from the front, but I got it done.

I've had a couple of leaks in the rear, shower and rain water, and the leak always appeared first in the middle of the carpet!

mayco 02-18-2015 02:30 PM

I dont think any of the supply lines run under the floor, at least I know they dont on my 310. They run along the walls from the pump location. Not sure on the 345 but mine are all concealed by furniture or closets. The head is plumbed from the pump down the street side wall. The shower hot water supply runs down the same wall and back, then around the back wall and then down the curb side wall. The cold supply line to the shower runs from the pump along the back back wall then down the curb side. There arent any supply lines that cross in the middle of the coach. It all looks to be factory installed.

mayco 02-18-2015 02:36 PM

The way the floor frame is built on the motorhome, you would be able to see anything running underneath I do believe. The only piping Ive seen under the floor is either waste line or propane.

KJRitchie 02-18-2015 02:49 PM

Check the flashing between the shower door frame inside the shower enclosure. Mine leaked and water would exit under the wood cabinetry to the hall floor. I removed the shower door, framing, threshold and flashing and applied caulking. Eventually I got it fixed.

Remove the access panel behind the shower faucet and see if it leaks.


Orlop 02-18-2015 03:08 PM

I had a similar experiance with my shower and it was a hairline crack in the pan itself ...... not sure how it got to the hall, but grinding it out and epoxy filling solved the problem.


tevake 02-19-2015 06:04 AM

Thanks for the good suggestions here,
I'll start with some caulking around the shower door.
Then re check the plumbing to the shower.

I do find it strange that water can travel under the carpet then show up some distance away.

Ah the learning continues, thanks for sharing your insight.

Cheers Richard

wxbuoy 02-20-2015 06:13 PM


Here is what I know. You pump is under the bed. If they are twins it is under the drivers side bed closest to the tank and water fill. The lines run up the inside wall of the coach. So it you have twins they run around the back under the headboard about 3 inches above the floor. If you have a queen or offset queen same thing except they start where the pump is located. If it is a twin to queen conversion this would be on the passengers side where the pump is.

The pipes follow the wall and go behind the shower. If twins you can see them. If a center queen (north south) they are hidden behind a false panel made of luan and covered with mouse fur. From there they run to the inside aft of the closet in front of the shower. You can remove the floor and then the panel and gain access to the shower control assembly.

To test where water is cumming form. Drain water lines. Dry wet area completely. Energize water.... and wait. an in-line pressure gauge will tell if you are loosing pressure or you can listen and see if the pump is coming on. One you don't have to watch (gauge) the other you sit there with a beer and wait. I kinda like the waiting game with a beer. if it doesn't come back it is not the lines.

Next put the sower wand close to the drain and run it for a while. If still no wet spot, then it is not a hairline crack or gap at the fixture fitting.

Then carefully spray around the pan and see if the spot appears. If it does it is the pan.

The other option is that the drain is not seated/sealed correctly. allowing water to flow between the pan and floor.

Either way the leak will flow along the wood under the carpet OR flow under the wood and above the layer of galvanized metal. When they built them they put a thin layer of galvanized metal over the frame and then laid the plywood on top of that. This was to keep road water off the plywood but allows water to get trapped and flow. If the wet area is the low spot where water naturally flows too, you will always see water there first since it is most likely degraded in that area. I have lots of pics of the systems "pre-Dave" if you wabt to see what they look like out of the factory.

wxbuoy 02-20-2015 06:18 PM

You can see the pipes in post 18 of this thread.... You can actually see everything!!

All times are GMT -6. The time now is 06:08 AM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.