Phantom Leak

[jdarwin]

Hi all. Ever since the Texas freeze last year we've had a phantom leak behind the convenience panel. I'm looking for suggestions on how to locate it.


During the freeze last February, our rig lost power and everything froze up. It cracked the faucets, toilets, water pump, low point drain valves, holding tank valves, etc.



We had it repaired. Afterwards I installed a 2 canister filter system. The filter add-on is not leaking. I did find the diverter sending water to the coach or fresh water holding tank leaking at a joint. I repair it.



Several weeks later I opened the storage hatch to find standing water behind the convenience panel. I checked the joints and couldn't find anything. The problem would randomly show up every few weeks to a month and then seemed to vanish. This past fall the problem started again. I thought the RV water regulator was bad (it was showing 90 psi) and thanks to this forum I installed a WATTS house regulator at the city connection and set it to 55 psi. Again, I thought the problem was solved.



We just got back from 3 months in Florida (only had the problem once) to find water again behind the convenience panel. I have wrapped the joints with paper towels and am checking the joints each morning. Yesterday, I filled the fresh water tank and we running off the pump to test it and those connections. This morning everything was dry.



I've started to make a diary to track what faucets and connections we're using in an attempt to isolate the problem. So far... no luck.



I had a neighbor suggest putting pressure on the system to force the leak. I'm not sure that's a good idea. I don't need to blow any joints/lines. A local RV repair tech said wrapping the connections/joints was a good idea.



So now I'm lost as to what to do next. When it leaks it doesn't seem to produce much water (maybe 16 to 24 oz). I have towels on the floor of the basement and as of today they are dry.


Any suggestions is appreciated.

[Daryles]

You are doing everything right. I would do exactly the same thing to find the leak.
Maybe let your water heater go cold. Then turn it on. The water will expand and put pressure on the pipes. Check for leaks.
Do you run on city water or from your freshwater tank?
We use the freshwater tank. We only turn on the water heater when we need it, then turn it off.
We turn off the water pump whenever we leave.
So far no problems.

[RipNC]

Any chance rain is driving in at that top corner of the hatch and running beside or overtop of the white convenience center panels? My gasket on that side is compressed wrong (not like the door side) and may be leaking in a driving rain (still investigating too).

PS: thanks to Ron for helping me find that potential leak spot!

[jdarwin]

We use the city water connection except when we're on the road.

[jdarwin]

Thanks, I'll check that out. It rained here 2 days ago but was dry the following morning.

[RMcNeal]

Since it seems intermittent, one guess would be to check the black tank flush line. Do you use it and does it hold?

[jimcol]

Leaks can be a real b to find. I'd recheck the pressure from the new Watts regulator. It's easy to do and will eliminate one possible culprit.

[jdarwin]

We do use the flushing system to clean our tanks. I'll check those lines when I flush this week. It rained here the other day. I didn't find any water leaking or signs of leaking at the hatch seals. I'll double check the WATTS also and report back. Thanks for all the help everyone!

[phillyg]

Before you hook up your water hose, put a couple of drops of food coloring in the hose. Turn on the water, then open one inside faucet (to get water in the pipes) for a couple of seconds, then shut it off. Start looking for the leak, particularly in plastic 90 degree and t-fittings.

[chessera2527]

it could be a cold water leak ,when i had big trucks and in the winter hoses might leaks a little and stop when it warmed up a little. I just were around and tightened all the clamps and the leaks stopped, you may have to do the same

[leemedic]

http://www.rvdoctor.com/2015/06/prop...er-system.html

[Dreamersandtravelers]

What is above the convenience panel?? Our shower is and though it was dry inside pocket door slide the drips accumulated below as we placed several bowls to locate what formed a puddle. Turned out to be shower hose was our culprit. After tightened we place tissue paper in area of pocket door slide to rapidly see each time we showered. No more leaks.

[Windjammer56]

We have also experienced water in the storage compartment intermittently. After much searching I found that the vacuumed breaker for the black tank flush was installed near the bathroom sink.. with careful looking you could see traces of water running back down the pex from the sink area and dripping on the floor of the storage. I replace the vacuume breaker and no more problems. Good luck

[pyoung47]

Lowes and Home Depot have male hose to air quick connect. Screw this into your city water inlet. Purge most of the water from your system and pressurize to as much as you feel comfy with. Use a squirt bottle of soapy water to test for a leak as you would a gas fitting.

[sonofcy]

I had the same sporadic leak problem. Then one day I just happened to be looking at the plumbing when a drop fell. I replaced the plastic fitting with brass shark bite and problem solved. I suspect a cracked plastic bit after we also had a minor freeze up.

[mboys]

I did the same thing Sonofy did. Got tired of trying to find the leak and replaced lines to panel. No problems after that.

[Flying Dutchman]

Many great suggestions here. I have a problem with me black water flush that I now know where to look. Thanks!
One other thing that may not have been mentioned in the responses yet. Perhaps check to see if it only happens when/after you use your water pump?
Hope you get it fixed soon.

[jdarwin]

Thanks to RMcNeal I found the leak(s). I double checked the WATTS and it tested at 52 psi.

Today I flushed my black tanks and found the leaks. They are both coming from the lines to the black tanks. The first leak is coming from the screw on connection behind the garden hose connection in the convenience panel.



The second leak seems to be coming from the check valve for the second black tank. This is gonna be a PITA to repair as I can barely reach it without dismantling the water system.







Any ideas to make this easier? Thanks

[Mikendebbie]

Jdarwin - I’m willing to bet that some the smart folks here will advise you to cut the white pipes down to a point that you can easily reach the pipe ends and plumb them together bi-passing the black vacuum breaker valve. Then use a hose-end backflow preventer on that tank flush. Proper terms are escaping me right now. I believe that black valve is the vacuum breaker for your (our - I have the same model as you) rear black tank flush. Someone will chime in with better instructions.

For what it’s worth the vacuum breaker valve for OUR model front black tank flush is located behind a small 10x10 access hatch in the sidewall of the lower closet where my red arrow is pointing.

[Carl n Susan]

Bypass the check valve, don't try to replace it in place. Cut the Pex lines going to it, use a couple of 90 degree connectors (Pex or Sharkbite) to connect the two ends, add a backflow preventer at the outside fitting and you are good to go.

On Edit: I see MikenDebbie can type much faster than i and suggested the same solution (a popular one I might add).