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Topic: delayed roof leak?  (Read 767 times) previous topic - next topic

delayed roof leak?

We had a bit of rain and the insides stayed nice and dry. Then, 2 days later, water in worrying amounts dripped from around the front AC grille. I haven't been able to remove it and look around in there yet. I replaced that gasket very recenty. Though i'd be the first to assume that I screwed up that install, I can't see how it would keep rain out while it's coming down and then hold it for 2 days before letting it visit the living room. So I have to guess that the leak is somewhere else and it takes 2 days for it to migrate to that outlet. I am very concerned.. but thought before I look for the closest facility that has one of those pressure-differential leak detectors, I'd mine the brain trust and ask if anyone else has had a delayed leak like this in their older Unihome to provide me with a start point to go lookin! Thanks. --Jay
Jay
1989 U280 SE, 36', 3208T Cat, build 3292

Re: delayed roof leak?

Reply #1 –
Jay,

Have you operated that AC unit since the rainstorm? Check to see if drain holes are open or drain tube plugged.

Condensation.

Ice buildup.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: delayed roof leak?

Reply #2 –
When was the last spent quality time on the roof carefully checking the sealant at all the roof penetrations.  I had a leak in a toilet room window that turned out to be a roof vent many feet away that had aged sealant that needed to be replaced.
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R

Re: delayed roof leak?

Reply #3 –
Rood leaks are the bane of my existence and I went over every square inch shortly after I bought it. I reckon I'll be doing that again, real quick. The front AC hasn't been used or I would have immediately accused it of not being potty trained. But today I plan on giving it a thorough going over...
Jay
1989 U280 SE, 36', 3208T Cat, build 3292

Re: delayed roof leak?

Reply #4 –
My guess is that it is the A/C seal. When you install a new seal the unit many times requires re-tightening until it is permanently seated. Just try that first.

The other thing to consider is when running the A/C in cool weather the older A/C units can freeze up since the don't have a freeze sensor. It may take some time for the frost to thaw and overflow into the coach.
The selected media item is not currently available.Kent Speers
Locust Grove, OK
1993 U300 SSE 40' (Restored at FOT 2009) Build 4323
720 watts Solar
6V92TA DDEC Silver Engine
2014 Subaru Outback

Re: delayed roof leak?

Reply #5 –
What Kent said......the first half.
1994 U280, Build 4490
Deming, NM.

Re: delayed roof leak?

Reply #6 –
the A/C gasket should be about a inch thick pre-sealed.  When properly sealed, it should be about a 1/2 inch thick.  And don't over tighten them as that will make them leak.  No other sealant is required to my knowledge.

Also, your in Washington state???  Lots of high humidity being pulled out of the air by that A/C.  Check your A/C's drain hose.  It could be plugged up and causing the water to back up and overflow inside - just a wild guess on my part
1994 U225
build #4514

Re: delayed roof leak?

Reply #7 –
Front AC hasn't been in use at all. But, it looks like I overtightened the front bolts. One of the corners had separated slightly and it may have come in from there and taken two days to fill the grille tray before dripping over the edge. Went ahead and put a new gasket in, and will retq the bolts in a couple days. The edge of the roof opening looks to have a nice tight seal on it, such that water from elsewhere is unlikely to show up there. Good thinking, as I bet FT was more concerned about leaks from there, migrating trhough the inside of the roof to elsewhere, and making it so that would not happen.
Jay
1989 U280 SE, 36', 3208T Cat, build 3292

Re: delayed roof leak?

Reply #8 –
Hi Jay,

The other leak cause could be any cracks in the roof A/C covers. Don't ask me how I know.
Jim Frerichs
2002 U320 42'

Re: delayed roof leak?

Reply #9 –
Remove the AC and build up the roof mount area use 1/2"x 3" plastic molding. Spray the area under the AC with the Roof Repair Spray (Home Depot) while you have it removed. Cut slits on the edge of the interior fiberglass roof panel to allow draining, careful I got wet.  Reinstall the AC, now the water will drain away from the unit, not to it, the AC weight causes the roof to sag.
Steve & Nancy Snow
1987 GV 40'

Re: delayed roof leak?

Reply #10 –
That's great confirmation! I was going to do pretty much exactly that. But I couldn't help but notice a puddle of water up there when I puilled the unit off the roof. It showed no inclination to move around. The bad corner in my gasket install was up front, and the coach is sitting slightly nose high. I leveled it as close to plumb as I could, sheeted off the opening, hosed some water up there, saw nothing flowing toward it.. so then I stood up there right near the opening from both directions and stiil the puddles didn't try to relocate down to the living room. The roof seems to not deflect even after all these years. Maybe later it'll need the buildup fix, but I guess not quite yet. Dang, they built 'em well.  At least I hope I don't need to do the buildup thing right now; it's raining again so I guess we'll find out soon enough.
Jay
1989 U280 SE, 36', 3208T Cat, build 3292
 

Re: delayed roof leak?

Reply #11 –
It's been raining pretty steadily and there are no signs of leaks, yay!
Jay
1989 U280 SE, 36', 3208T Cat, build 3292