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Topic: Roof mount A/C unit leaking after gasket replacement on 1997 U290 (Read 613 times) previous topic - next topic

Roof mount A/C unit leaking after gasket replacement on 1997 U290

We just had a RV handyman replace the original gaskets on both roof mount Penguin units with new neoprene gaskets.  The aft one has stopped leaking when it rains but the forward AC still has water coming in during hard rains...Maybe as much as a cup in a couple hours of hard rain here in Athens AL.  The tech did tighten up the hold down bolts....However we understand that a styrofoam drip pan can crack letting water in even with good gaskets...also, is it possible a drain hose is plugged or adrift?  Can anyone give us an idea how to fix and what to check.  Unfortunately I am away for another 4 months so my wife will be the one to fix this.  The unit did cool just fine last year and I don't remember any leaks...Hate to put a new unit in just because of a leak.  Note that this leak is with the unit off in heavy rain...Not sure if it will be a problem when running as it is too cold to really test now.  Any advice appreciated!

Carl and Kathleen...Athens Alabama.
Carl and Kathleen
Killeen Texas
1997 U270

Re: Roof mount A/C unit leaking after gasket replacement on 1997 U290

Reply #1 –
Since the unit is not running and the unit has a leak while it is

raining I would say you do not have an ac problem but a problem

with the new gasket. The installer of the gasket should return and

finish the job.

Carter-

Re: Roof mount A/C unit leaking after gasket replacement on 1997 U290

Reply #2 –
If your AC has the four nuts and washers holding the shroud on, then is it possible that water is migrating around the nuts/washers down into the coach? I had it happen to our rear AC so all I did was cover the nuts and washers with caulk. Problem solved.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Roof mount A/C unit leaking after gasket replacement on 1997 U290

Reply #3 –
Carl,

I found that cracks in the shroud will let in lots of rain water. If your shrouds are older and brittle, then removing and handling then invites breakage. As a repair I have caulked mine on the inside.

Jim

2002 U320
Jim Frerichs
2002 U320 42'

Re: Roof mount A/C unit leaking after gasket replacement on 1997 U290

Reply #4 –
And if you do caulk on the inside of the shroud, caulk the cracks, not where the shroud sits on the AC unit or anything else. If you do caulk in those areas you will most probably have to break the shroud apart to remove it. The caulk up under the shroud will act like glue and, with the shroud being brittle from exposure to the elements, most likely crack even more.
I was fortunate this summer in that I picked up an AC in great shape for $25 + tax ($26.83) and used the newer shroud. My old shroud is stored up in the garage attic in the event of breakage.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Roof mount A/C unit leaking after gasket replacement on 1997 U290

Reply #5 –
On my old Foretravel I used the tape that is discussed in posts on the Forum. White and sticks to anything used for roof leaks until permanent repair.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Roof mount A/C unit leaking after gasket replacement on 1997 U290

Reply #6 –
Don't most of those ACs have a torque # on the bolts when the gaskets are replaced? If you have "drain pans" that daylight down below, you are lucky, we don't. I used to take a small compressor and blow the drain back up to the pan, then clean the debris.
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'

Re: Roof mount A/C unit leaking after gasket replacement on 1997 U290

Reply #7 –
These are all great solutions but the man is away (at sea?) for four more months

and he is wanting to get the help for his wife back here in Alabama.

That is why I suggested she get the repairman back and fix the problem.

Carter-

Re: Roof mount A/C unit leaking after gasket replacement on 1997 U290

Reply #8 –
Thanks...Actually I am in Afghanistan...I know the shroud was brittle and discolored...Will have it checked for cracks and look for a replacement.  Am I correct then in assuming leaks can only come from a bad or failed seal or from a cracked plastic cover?  Or is there another possible place it can leak from in a rainstorm?  Thanks for all the advice.  One lame idea I had was to just saran wrap the whole thing till I get home or it gets hot enough to need the ac...Like they do suitcases at the airport....
Carl and Kathleen
Killeen Texas
1997 U270

Re: Roof mount A/C unit leaking after gasket replacement on 1997 U290

Reply #9 –
Yes, I'd say in order to diagnose a potential seal issue, it would take two people.  So I'm with you, either cut a tarp or just use a large, trash bag and tape it with painter's tape down to the roof.  And wrapping it in saran wrap wouldn't be a bad idea, just for extra protection. But either way, I would definitely add the trash bag over that and tape it to the roof, otherwise, especially if it is the seal, water will migrate to the leaky point.

And, if possible, I'd let it dry out well before sealing it up.  You don't want to trap moisture anywhere.
Jennifer
2003 36' U295 (# 6070)
Thousand Oaks, CA

Re: Roof mount A/C unit leaking after gasket replacement on 1997 U290

Reply #10 –
Carl,

Thanks for your service. I know it has to be frustrating

to have things break so far away. Hope someone comes

to the rescue.

Carter-

Re: Roof mount A/C unit leaking after gasket replacement on 1997 U290

Reply #11 –
Just read the replies and "painters tape comments". If this is to hold down a cover over unit to keep rain out I would suggest that it is held down with something else maybe even a few heavy blocks or? as the tape will come off with moisture after a while.
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 mount A/C unit leaking after gasket replacement on 1997 U290

Reply #12 –
Quote from: John Haygarth –
Just read the replies and "painters tape comments". If this is to hold down a cover over unit to keep rain out I would suggest that it is held down with something else maybe even a few heavy blocks or? as the tape will come off with moisture after a while.
JohnH

I once tried to bag over a leak to buy some time to fix.  Put several layers of black-leaf bags + tape.  But then warm weather started evaporating moisture that was trapped inside.  Even though the exterior layers of bagging were dry, the interior stayed moist.  Won't do that again.
James
w/ DW Erin, sons Gideon and Tobias, cats Oscar & Oliver
Fulltime 1999 U270 34' #5508