Mildew smell

[GREGW]

We have a 2013 Keystone Cougar 28 RLS. From Jan to April we traveled along the California/Oregon coast in very wet weather. We had no leaks but a lot of condensation. Coming north to Alaska in May we began to smell a moderate mildew odor. The odor is concentrated near the TV console and the side wall to the slide. Any thoughts on getting this fixed or doing it ourselves? What is in the wall between the tv and the bathroom? We took off the trim on end of slide and the particle board underneath shows slight water damage on bottom 4 inches. (We had previously taken off trim by doors and filled air space with foam spray to stop extensive condensation there.)

[Campy]

I recently had a similar issue and due to a completely unrelated repair found my problem. We have been noticing a musty/mildew smell but mostly in the storage compartment and around the steps going up to the bedroom (stairs have vents to front storage) after a recent trip we hit something on the road and managed to tear off the fresh water tank drain. Upon dropping the under belly plastic we found it full of stinking water! Clearly its rain water thrown in by traveling and no way for it to drain so it just lays in there in the low spots and stinks. We also found a bunch of "foil bubble wrap" wadded up in there,... polar package?? Well it was useless like it was but I don't camp in the winter anyway.

[jsmith948]

Originally Posted by Campy

I recently had a similar issue and due to a completely unrelated repair found my problem. We have been noticing a musty/mildew smell but mostly in the storage compartment and around the steps going up to the bedroom (stairs have vents to front storage) after a recent trip we hit something on the road and managed to tear off the fresh water tank drain. Upon dropping the under belly plastic we found it full of stinking water! Clearly its rain water thrown in by traveling and no way for it to drain so it just lays in there in the low spots and stinks. We also found a bunch of "foil bubble wrap" wadded up in there,... polar package?? Well it was useless like it was but I don't camp in the winter anyway.

Had a similar problem - ran through a torrential downpour from Carlin, NV to Jackpot, NV. Later noticed water dripping from underneath the trailer. When we got back home, I lowered the underbelly to find a couple gallons (or more?) of water. Found that there were gaps along the edge of the Coroplast where it meets the frame - especially in the areas near the wheels. Deduced that the water was from road spray entering these gaps.
A medium sized bottle of alcohol and about 3/4 of a roll of Gorilla Tape and the underbelly is sealed. No issues since. FWIW

[parkgirl]

You may have a leak in your slide. We had the same problem and there was dampness in the storage under our dinette that we didn't notice for awhile until there was a slight smell. Slide-out leaks are apparently quite common and the source of it is the metal trim piece that is screwed in on the sides outside at the bottom of the slide-out. There should be a silicone seal along the top of that trim piece but when it wears off the water falls down the side of the slide, gets in under that trim and trickles down into the inside of the trailer. Our trailer also is a 2013. I did contact Keystone about what to use to caulk that trim and they said they originally used silicone and I should use silicone, making sure to clean it well first. (There are arguments on this forum about the cons of using silicone--never use it on the roof of course--but I chose to go with Keystone's instructions.) After I sealed it up with the silicone, the problem was solved.