Air Conditioner Roof Leak

[lewster]

Originally Posted by fmrcaptevil

I just learned this the hard way: if you think your a/c mounting bolts need to be tightened, be extremely careful.....40 to 50 inch/pounds (as recommended by the generic Dometic paperwork that came with my trailer) is WAY too much.......so as usual, Airstreams are different.

I don't use torque specs for tightening a roof air, as almost every situation is different and 'generic' specs are just that.......one size does NOT fit all! The sealing gasket should be compressed to 50% of it's original height to obtain a proper seal.

[Aviator]

The drain tube comes out in the wheel well. Just look for a few inches of hose sticking down.

[bramer]

Perhaps this will help. My 2010 31D Airstream flooded water when we ran the heat pump...didn't when we ran the A/C. It was repaired in Paso Robles while we were on a trip (two weeks in Paso Robles).

The unit needed to removed and the pan checked to determine the water footprint. My unit had cracks in the heat pan and Dometic unit. Dometic, AS, and Paso Robles had a joint phone conversation while looking at pictures. Dometic replaced the unit. It is important not to use power tools when tightening the unit!!!

I would suggest taking it to a dealer and have them remove and check the the pan. It would be helpful for them to actually see it leak to help trace the problem. It may also leak when running the heat pump. We purchased in August and didn't use the heat pump until late September.

Hope this helps. Paso Robles was super in solving the problem; Jana was Superb! She could also help explain the problem that triggered a unit replacement. Northwest Airstream started the repair and didn't finish it because of our trip schedule being tight. They didn't a wonderful job in coordinating a continuation of the warranty work with Sky RV.

[noreen&sal]

Thanks for the loc. of the drain tube. Will see if I can blow it out. Hope to be trying it in Jan. in Fla. Sal.

[BillB44]

Thanks all. Bramer, ours is purely a rain-related leak. No issues when using heat pump or AC. Just when driving thru heavy rain. (Which happens a lot in the Northwest!) The 'Spud is under a roof now, in storage, but we'll be taking it to an AS service shop (C & G) in SoCal in Jan or Feb to get to the bottom of things. I hope. Will post an update then.

[BillB44]

If anyone's still following this thread, we're back and this week we take the Silver Spud into C & G Service Center to have them diagnose and repair the AC/roof leak. Will post outcome when we learn it.

[fmr.capt.evi]

Yes, looking forward to hearing about it.

[tarheel1972]

I am on the hook to fix my AC/rain leak on my '72 Ambassador. The Dometic AC is a replacement unit that is only a few years old. But during a rain storm, it leaks like a over watered horse.

I can see various suspect seams in the area under the and around unit that I want to attack with Vulkem.

My plan is to unbolt the unit, lift and block the it up high enough to attack all the seams and such. Blocking it up with dunnage.

Any thoughts here?

[BillB44]

Well, after 269 miles round trip, we have the 'Spud back from C & G and they claim it is fixed. They did NOT remove the AC or work on the roof at all. Rod, the owner, said Airstream instructed him to remove the shroud from INSIDE the trailer and to seal around the ceiling from there. It has been stored under cover since we got it back so I can't report with any certainty whether the leak is truly fixed or not. C & G says they tested it with a lot of hose water but I won't feel comfortable until it's been tested in a good ol' rain storm rolling down the highway. That should happen in late April when we hit the road for three weeks. Stand by...

[HCR]

Mine (Duotherm) leaked from vent and after exploring discovered the pan was cracked and had been repaired (sort of) with caulk AND, somewhere along the line the gasket was missing--either from initial install or after repair. Replaced pan and added a gasket and problem solved. Pan probably cracked in the first place because the gasket appears to dampen vibration as trailer is going down the road and without it the pan (probably) vibrates excessively.

[bramer]

I agree you should have another AS dealer look at it. My 2010 30D's pan was also cracked along with the AC unit. The correction was to replace the entire unit (AC and Pan). If a mechanic or installer used a power tool to tighten the result can be a cracked pan. It is important to tighten only by hand according to the AS dealer that fixed ours in Paso Robles. Ours was over torqued somewhere along the line (factory or dealer). Just a thought.

[BillB44]

Thanks HCR & Bramer. The fact that yours, Bramer, is also a 2010 really has me concerned. We're getting the Silver Spud out of storage next week and heading to Utah for three weeks. I'm not brimming with confidence that it won't leak again if/when we get into any rain. Guess I can just always hope for sunny weather wherever we go. Except we live in the Pacific Northwet most of the year. :-)

[BillB44]

Good news to report. We just got back from a great, 2,600-mile, three-week trip to five National Parks in Utah and hit some serious rain in the final days. And....ZERO LEAKS! (The trip blog & pics are at bbkb.wordpress.com)

We are very happy. Let's hope it stays this way for years to come!

Thanks to all who chimed in.

[Clar7135]

Bill,
I'm glad you got your leak fixed up and repaired. Currently, I'm dealing with a similar issue on my 05 dometic ac unit. I removed the inside shroud and the metal plate held on by the 3 long bolts. (will tighten back up with hand when done.) I found a very slow leak coming from a small crack, about the size of an eyelash coming from the black pan right where it hooks up to the hose. It seems to only leak when in rains...I want to repair it, but I have a few questions:
1) should I remove and replace the entire black pan ( and all of the factory grey caulking)

(if so, I can't find the part # of the drip pan)

2) or just find some sort of repair for the crack (epoxy?)

3) is to cough up $ and take it to the dealer to repair...how much did you spend getting yours fixed?

4) Is it normal for water to find its way into the drip pan when it's raining in the first place? Or should I be looking for an additional crack/leak from the exterior?

Any input helps. Thanks guys

[Edhopkins]

Any help in we are discussing a Coleman roof unit. I have a 1986 25' Excella we just purchased. Airstream is like new except the ac leaks - both when it running and not raining and when the ac is off, but it is raining. Just started the rain leak, we took our Airstream on a maiden voyage from Destin, Florida to Ct and back - ten day round trip. Rain leak started when we returned home. The a/c leak first appeared when we hooked Airstream to shore power.
Thank you for any and all replies..

Ehopkins

[Foureagles]

Well, I'll tack my woes on, since the OP's problem is fixed (thanks BillB44 for sticking around to post the resolution). I have a '71 Overlander with a Coleman A/C unit. Around 10 years or so ago, the interior control panel was taken down in preparation for removing the unit (going to Colorado -- wouldn't need it). The trailer was moved a few hundred yards with the A/C unbolted, but it never leaked before or after. Now that I'm back from Colorado (never took the trailer) I decided to stick the control panel back on and bolt 'er back up. Surprise -- the A/C still works!

But now it leaks very badly in any substantial rain -- have a tarp over it right now. With the interior cover off, it appears to be leaking everywhere, or at least coming in unseen and splashing everywhere. My first thought was that tightening the mounting bolts opened up an old, brittle caulk seam, but reading this thread leads me to think that this is unlikely. I'm now guessing that it's a cracked drain pan, and/or it possible shifted out of place when the trailer was moved with the unit unbolted. By the way, condensate does run down the side of the trailer, and nothing leaks inside when the A/C is on and it's not raining.

Thoughts? Thanks in advance!

[DreamStreamr]

Can't tell percentage compression on the gasket - wonder if a gap measurement (between roof and roof unit might help those of us "re-tightening?"

Chiming in late to this old party. Foureagles, did you figure yours out since last July? Just curious, since mine is DuoTherm and perhaps not at all same.

My 2005 CCD25 started leaking a month ago. Only leaks when raining. Initially thought cracked corner on cover but caulking that, in place, didn't change the leak. Leak is coming from forward road side hex bolt head above the cabin air filter. We pull the filter, place a 1 qt pan on floor and we're good.

Took off outside shroud today, cleaned and inspected, all looks good. Took off inside shroud, drain pan and tube connection all appear sound. Thinking I'll try Lewster's rec for gently snugging mounting bolt.

[DreamStreamr]

Okay, followed Lewster's rec two days ago on compressing the air conditioner's roof gasket. The a/c mounting bolts all three (2 front, 1 center rear) felt pretty slack. I used 1/4" ratchet with extension, and turned each from under the a/c inside the cabin about two turns. They felt smoothly tighter. Can't visualize the amount of compression or gap change, but could tell I had taken up the slack.

Handily we had an entire afternoon and evening of rain yesterday. No leaks!

By the way, first time I've ever removed the a/c covers inside or rooftop. Far easier than I imagined although the outside one won't suffer many procedures without cracking thru on the flange corners. How was the roof unit after 11 years of zero inspection and maintenance? As bad as you can expect.

I removed remains of an attempted bird nest and a lot of surface dirt. Most striking and guilt inducing is the complete 1/4" thick filter mat that had accumulated on the condenser coils. Fortunately the lint easily pulled away, leaving pretty good looking fins. I'm sure the campgrounds would see lower power bills, if only we ever used our a/c. Honestly, we don't have two hundred hours on it.

It'll cool better now, though. And doesn't leak into the cabin, for now. Thanks, Lew. I owe u yet again.


Dreamstreamr
2005 International CCD 25SS
http://Dreamstreamr.com

[lewster]

Originally Posted by DreamStreamr

Okay, followed Lewster's rec two days ago on compressing the air conditioner's roof gasket. The a/c mounting bolts all three (2 front, 1 center rear) felt pretty slack. I used 1/4" ratchet with extension, and turned each from under the a/c inside the cabin about two turns. They felt smoothly tighter. Can't visualize the amount of compression or gap change, but could tell I had taken up the slack.

Handily we had an entire afternoon and evening of rain yesterday. No leaks!

By the way, first time I've ever removed the a/c covers inside or rooftop. Far easier than I imagined although the outside one won't suffer many procedures without cracking thru on the flange corners. How was the roof unit after 11 years of zero inspection and maintenance? As bad as you can expect.

I removed remains of an attempted bird nest and a lot of surface dirt. Most striking and guilt inducing is the complete 1/4" thick filter mat that had accumulated on the condenser coils. Fortunately the lint easily pulled away, leaving pretty good looking fins. I'm sure the campgrounds would see lower power bills, if only we ever used our a/c. Honestly, we don't have two hundred hours on it.

It'll cool better now, though. And doesn't leak into the cabin, for now. Thanks, Lew. I owe u yet again.


Dreamstreamr
2005 International CCD 25SS
http://Dreamstreamr.com

DS,

You only have 3 mounting bolts????

I have seen that used on flat roof SOBs but on a curved roof Airstream??

If you look at the rear mounting bracket, there are 2 foil covered spots directly in line with the front bolts. There are also threaded inserts above them on the unit's base pan.

I would highly recommend that you find another bolt (1/4-20) and use the outside anchor points. I've seen too many leakers because of them being too cheap (Airstream or Dometic) to add the 4th bolt!!!!


Lew Farber
RVIA/RVDA Nationally Certified Master Tech
ABYC Certified Master Marine Electrician
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center*AMS Lithium Batteries
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541-490-6357

[cwf]

Lewster, thanks!! The 4th bolt made a huge difference!!!