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Topic: Roof Rail Condensation U320 (Read 534 times) previous topic - next topic

Roof Rail Condensation U320

Hello,
 I own a 1995 U320 and have a condensation issue coming from the curved rails at the side of the roof.  I had so much it was dripping down off the rails inside the rear cabinets on both sides behind the wood panels. So I wondered if I should use some spray foam or ?? That roof rail is like a tunnel for wires and water that ends up in the rear of the coach. I resealed all the roof cap screws thinking it was problem but I'm still getting dampness in that cabinet. I even bought a small dehumidifier. HELP!! 
Steve

Re: Roof Rail Condensation U320

Reply #1 –
There is a strip of metal and I would unscrew and Rebed all the screws
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: Roof Rail Condensation U320

Reply #2 –
Steve,

Are you talking about the extruded aluminum piece that is the joint between the side wall and roof sections? If so here is what we do in winter time to help out. We leave our cabinet doors open, run a dehumidifier, leave vent in kitchen area open, and most important always run exhaust fan when showering.  This will help with your dew point that you are dealing with. 

The foam you are thinking about is not a good idea as you may need to pull some wires in through that extruded aluminum piece in the future. I know of one person that has already attempted to fill this area with foam and that coach will still sweat due to the good thermal transfer aluminum has.

Pamela & Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Roof Rail Condensation U320

Reply #3 –
We may be talking about two unrelated issues:

Water LEAK from the outside.

Control of humidity on the interior.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Roof Rail Condensation U320

Reply #4 –
I would do as John S mentions. CHECK very carefully all the screws and along the trim both sides. There may also be water coming in from the clearance lights so check them too and caulk the screw heads.
JohnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Roof Rail Condensation U320

Reply #5 –
Our coach had a similar problem ( or should I say "I" had ) until we realized you can't heat, cook or shower in the coach without VENTILATION. You hate to have heat going out the window but the condensation at the inside roof rail stoped completely when we started running fans and opening ( just a hair ) windows.      We also put a couple of dry-z-air canisters in strategic spots but they don't seem to be filling up.
Robert and Susan
 1995 36' 280 WTBI 8.3 3060r
 1200 watts on the roof, 720 Ah of lithium's
 Build # 4637. Motorcade # 17599
        FMCA  # 451505
        18  Wrangler JLUR
 

Re: Roof Rail Condensation U320

Reply #6 –
Check all the marker lights along the roofline and your rear AC mount for cracks or leaks. Water does travel once it gets inside.
1993 U300 40ft GV SE
Build # 4344