Water Leakage Near Fresh Water Tank

[Ranger16701]

Hello,
I am hoping someone can give me some advice. I have a 2015 Coachman Freedom Express 29SE pull behind RV. We have not used it since last year, and have recently pulled it out of storage for this year. Yesterday, when I was de-winterizing it, I noticed water leaking. I had flushed the system by filling the fresh water tank and then draining it after I turned the pump on and let the water run until it was clear. Then, I decided to sanitize the system as it says to do in the owners manual. I added the bleach solution as the manual said to do to the fresh water tank and continued to fill the tank until full. I then let the tank sit over night.

The next day, I went out to the RV to drain the tank and when I did, I noticed water dripping from around the fresh water tank drain tube, all around where the tube was 'foamed' into the flooring material, underneath the RV. The water is not dripping from the tube itself, but coming out around the tube where it was foamed into the floor. I went under the RV today and saw that the floor behind the tube seemed to be a bit bowed, and when I lifted up a bit on the floor, water started dripping out the sides of that bottom protective flooring (not the floor inside the RV, the floor that is attached under the RV to keep the elements out.

Does anyone know what could be causing this, and how to fix it? Being recently laid off and a disabled veteran, I would rather be able to repair this myself as opposed to taking it someplace for a repair. Any help would be greatly appreciated.
Thanks,
Mike

[Splitshaft]

I’ll offer my advice and experience. I had purchased a new pull trailer. That winter and under warranty, the underbelly filled with water, not from the fresh water tank over the sagging underbelly. Water entry into and under the floor was from both the water heater bezel door frame that was not sealed to the tin housing face of the water heater and also from the exterior AC outlet, both leaking water into and under the floor of the coach. The underbelly cover had to be removed, the wood dried, and new insulation installed.

If the water was noticed when bringing the unit out of storage, it could also possibly be from rain water intrusion as well as the fresh water tank filling and flushing operations. Regardless, the moisture should be removed from under the floor if possible, if moisture is under the floor. There are multiple locations of the fresh water tank/system leakage, the tank its self, the fill tube and fill tube connections, the vent tube and vent tube connections, the drain tube and drain tube connections, and the outlet to the water pump and its connections to include the pump and water lines themselves.

If I suspected a water leak in the freshwater system. I would apply a very slight positive pressure to the fresh water tank and measure the pressure with a manometer for measuring water column pressure of fuel gas systems. If the small positive pressure was not maintained over time, the fresh water system is leaking and the leak needs to be identified. If the fresh water tank and piping held pressure, then the water intrusion could be from rainfall. RV’s are notorious for water intrusion at every penetration in the roof and sidewalls. Flexing and movement that occurs traveling over uneven roadways has a way of causing seams and seals to fail to include piping and other connections to loosen.

Since loose fasteners are often all over a newly constructed RV, hopefully when the fresh water tank was installed in the coach, it was not set on a loose screw some assembler dropped causing a hole to wear through the bottom if the tank.

Drying the coach out to prevent mold and mildew followed by softening and failure of the floor is the most critical thing in my opinion at this time. Once dry and before resealing the underbelly, the leak needs to be identified and repaired. Depending on the foam material mentioned, if it is just a spray foam, I would just dig it out to gain access to the drain tube and valve.

Hopefully the coach is insured, if there is insurance, the insurance should pay to repair or replace the coach depending on the extent of the damage once opened up.