Water Damage to Floor of 3210

There are two soft spots in the floor of my Cyclone 3210 from moisture damage. The first is located at the corner of the entrance door, right under the refrigerator. There are also water stains at the bottom of the entire refrigerator cabinet. Almost directly across, on the other side of the unit, another soft spot has appeared at the front of the opening for the slideout. There has never been standing water in either location, the damage is limited to the subfloor only, and there is no other water damage anywhere that I can find. The best explanation that I can come up with is that water is coming in a tiny breach in the vapor barrier on each side. Both leaks are located directly in front of the wheels, and both locations have an opening through which water coming off the front tire at high pressure could penetrate. Has anybody had a similar problem? Can anybody offer an alternative explanation? Obviously, I need to be sure that I have found the leak, and repaired it, before I fix the floor. Any input is appreciated.

PBAJ, my favorite sandwich by the way. Your theory sounds good. If you've had no other leaks and no sign of intrusion or damage from other sources, I'd say you should be good to go.
What year is your Cyclone? In the early years of Heartland, there were problems with water spray coming up through slide out corners. They incorporated a corner seal of block foam and rubber to prevent this. Maybe your's is missing or an earlier model without the corner seals?

Thanks for the reply. My rig was built in December, 2007, although it is a 2009 model. There is a plastic cup screwed into each corner of the opening for the slideout, with a rubber seal on it. The one where the leak is located was very wet inside when I took it off, the other appears to be dry. After a drenching downpour that lasted about two hours, I checked the seals on the slideout, and found them to be dry. There was no moisture around either soft spot in the floor. The source of the water is still a mystery, but I am thinking about cutting out the rotted wood, and temporarily replacing it. My thinking is that I can leave the replacement material accessible, and check it regularly to see the conditions that cause water to penetrate the exterior shell. In order for this to work, I will have to cut the linoleum, pull some of it up, and replace the wood from inside, being careful not to damage the exterior vapor barrier in any way. Does this sound like a good idea to you?

PBAJ, that sounds like a good plan. Maybe once your into the damaged area, you may be able to determine the area or direction of intrusion. Good Luck and keep us posted.

I have found the occasional leak by our fridge when washing the trailer. Seems too much hose action by the outside fridge vent will have water intrusion under the fridge and out into the main area.

I haven't found the leak area but I solved the problem by using the left side LevelUp jacks to tilt the trailer to help water drain while washing the rig.

Time to close out this thread with the end result. The water damage on the right side of my Cyclone 3210 was the result of penetration through the furnace flue. It became obvious when I removed the outside cover, and pulled up the floor. I had checked this possibility out when I first noticed water inside the coach, about two years ago, but there just wasn't enough moisture to be sure what was going on. It would have been smart to stay on top of it, as I probably would have figured this out sooner, but chances are good that I would be replacing some subfloor regardless.

The left side is a different story. A gaping hole in the corner, at the front of the opening for the slideout, allowed moisture to seep in under the carpet in the dining area. The carpet completely concealed the problem until the floor rotted out underneath it. I'm still not sure how the water found it's way in, but the entry point is obvious, and the result of some very poor workmanship. Not being an experienced RV tech, I really don't know if I fixed either leak, but both areas are dry for now. Any input from more knowledgeable RV DIY, or professional techs would be welcome.

Speaking of RV techs, when I picked up my Cyclone from the dealer, the RV tech said something that gave me a sick feeling, and I have never forgotten: "It's not if your RV leaks, it's when."

PBAJ said:

Speaking of RV techs, when I picked up my Cyclone from the dealer, the RV tech said something that gave me a sick feeling, and I have never forgotten: "It's not if your RV leaks, it's when."

Click to expand...

This is somewhat a true statement for all RVs, both towable and drivable. We really have to inspect regularly. These beasts bounce down the highway and you know how wonderful our roads are.
Regarding the leak around the slide out. It might be a good idea to have the slide alignment checked. At the very least, try to determine if that corner foam block is doing it's job.