Mystery Leak

[Cujonaut]

I keep finding mystery puddles in my pass thru storage area. I checked all the lines, connectors and drains and can't for the life of me figure out what's causing it. It won't appear for several days and then one morning it will just be there. I can't find any signs of water seeping anywhere along the ceiling or walls. Based on the pictures the water appears to seep up from the floor and hug the bottom of the wood panel that separates the storage area from the plumbing fixtures, water heater and furnace. Has anyone had a similar problem before and found the cause?

[Jagiven]

Have you had rain or heavy dew before you seen it?

I had cargo hold door that had a bad gasket. At first it looked fine, but it was twisted at installation, and caused a leak, when it rained just right.

My favorite method to find a difficult water leak is with toilet paper. When it gets wet it get wrinkly, and changes texture and look when it dries.

Take a few squares, and spread them out. I tend to place a few on pipes, secured with a piece of scotch tape. On the floor in places. You have AL trusses over head. Maybe a piece or two on the truss, to see if water is flowing along a truss then dripping.

Is the water always in the same location?

You can see dried water stains up high on that panel. Takes a lot of ground water to soak up that high. Might be coming down that panel.

[PaulB12]

You have a lot of plumbing on that back wall, I'd start there. Water travels in wierd ways!

This drawer was absolutely dry when I removed from tt trying to find a leak. See water on floor and wet drawer?
Never found leak because there was never one!
The only thing me, friends and neighbor could figure out that there was something a previous owner had spilt and dried. Humid weather would absorb until it couldn't hold any longer and then weep out!
Built a new drawer using old front and rails and everything has bee fine since.
Not saying this is your problem.....but????
Happy water sleuthing.
PaulB12

[Bar-OneRanch]

I had a mystery leak and would find water on my chairs in the storage area. Mine turned out to be a drip from the fittings on the backside of my shower faucet working their way through the trailer and coming out 2-3 feet farther forward of the faucet.
Good luck
Chris

[Cujonaut]

Originally Posted by Jagiven

Have you had rain or heavy dew before you seen it?

My favorite method to find a difficult water leak is with toilet paper. When it gets wet it get wrinkly, and changes texture and look when it dries.

That's a good idea to use the TP, I'll try it out.

I sat and watched the plumbing yesterday with the water running for a good solid ten minutes and nothing. I came out that evening and there was a puddle. This time i noticed a pex fitting leaking behind the main plumbing box. It wasn't leaking earlier, maybe the decrease in temperature caused it to start leaking. It dropped about 20 degrees F between the time I first looked at it and then saw the leak.

[Cujonaut]

Originally Posted by Bar-OneRanch

I had a mystery leak and would find water on my chairs in the storage area. Mine turned out to be a drip from the fittings on the backside of my shower faucet working their way through the trailer and coming out 2-3 feet farther forward of the faucet.
Good luck
Chris

Same thing happened to me a few months ago, but it was the bathroom faucet and it was pretty much a straight shot from the leak to the storage area.

I did check the shower fittings and there wasnt any evidence of water leaking.

[RogerR]

Mine ran down the window corner and disapeared behind the wall, coming out in the storage area below the window but more than a foot left of when the leak was. Water travels sideways sometimes.

[craigav]

Just as a thought to where a mystery leak could come from. In the winter time when the humidity is high inside the rv, the windows (single pane) will form condensation. My thought here is that anywhere inside of the RV where you have a wall that is not insulated as well as the other wall areas, could also be a source of condensation and would end up running down to the floor level. Just a thought, I would only consider this though if you also see condensation on a window first... ~CA

[atlantaM3]

I had a similar issue with a very intermittent leak into the basement. the culprit was the tub drain. It had popped of the fitting to the tub. During a shower, the water flow was low enough that it still would drain via the plumbing. When the little one took a bath, it would be enough volume to spill past the fitting. the water would fall down onto a trim panel across the top of the basement space under the tub, then drain down the basement wall trim.

Generally, the little one took a bath when it rained, so I though there was some goofy roof leak. Took taking things apart to find the root cause of the problem.

[Marine71-76]

We had water in our bedroom window frame and later in the basement - still under warranty. Of course the dealer never ever found anything. DW even left the paper towel in the window frame to show them. While camping during a good steady rain, the basement had water again. Turns out there was a small gap in the caulking on the rim of the roof - and this was after the dealership inspected the roof! The unit wasn't even a year old at the time & we had dropped it off for several warranty items, including the water.

[Cujonaut]

Finally went ahead and replaced most of the damn flex hoses. It baffles me why Jayco would use this type of hose with the wrong connectors. Replaced the water heater cold inlet and hot out hoses. I did learn you can use a dremmel with a cutoff disc to remove the pex pinch clamps in tight spots. Also, I used a heat gun to bend the rigid pex pipe for a better fit. End result isn't super pretty, but it doesn't leak. Thanks for all the replies, i learned quite a few things to look for when determining leaks in the future.

[PaulB12]

Sometimes it takes manual flexing and wiggleying to make them leak.
PaulB12

[Cujonaut]

Update - Still no leaks at any of the pipes and connectors I replaced. I did notice a small puddle of water underneath the water pump connector. It's the only plumbing in the trailer that still has the flex hose. I'll replace it with PEX this weekend.

[JFlightRisk]

Originally Posted by Cujonaut

I'll replace it with PEX this weekend.

Nothing wrong with doing that, but don't be surprised if the pump noise is more noticeable afterwards. The flex line helps diminish the vibration. Just a thought to run by you.

[Extreme]

I had the same issue in my fifth wheel and after removing panels I found the drip came directly from the vinyl 3/4 “ nuts which are directly in the back of the water heater. I tightened them and it stopped only to start again a while later until a mobile repairman came in and replaced the silicone washer inside the fitting. Something to do about warm and cold temp changing tightness of plastic fittings.

[DadBodMarathonRunner]

Mystery leaks are the worst. Not sure if it rains much there but I had an issue with the door latch to my pass through. The metal catch had 2 screws holding it in place. The rain would puddle around the latch and then leak around the seal, right into the wall and then out to the floor.

[JDug66]

I had the exact same thing, puddle in the middle of my pass-through with wood wet between floor and framing. I found a small (1/4" x 3/8" ) section on the exterior top right window seal where the black foam seal (between aluminum skin and window frame) had either not been cut to fit or had slipped down leaving the interior open (visible insulation). It happened to be directly under the run-off from the retracted awning. My guess water ran down the inside of my wall and out on to the pass through floor.

[nynethead]

I had a leak and it would then drip outside. It ended up being the trailer was not level side to side an was coming from the shower. Somehow it would leak, not sure how but if trailer is level it doesn't happen.

[mlitt55]

Mystery leak are the funnest. #1) turned out to be a drip from the fitting on the backside of my shower faucet, dripping straight down. Only showed up when HOT water was running thru that piece of pex. #2) is a bad crimp on one of the white flex hoses. Still figuring out how to change this one. Difficult location. 2019 Jayco Eagle HT
Good luck

[Patjjensen]

We have a 28.5 RSTS fiver and our shower is above our passthrough and if I allow water from the shower to gather on the bathroom floor the water will leach under the shower pan and then drip down into the pass through area. So, keeping water in the shower prevents “leaks” into the pass through area.