caulk/sealer

[wrbaron]

I have a small leak at the air conditioner. instead of having unit pulled and reset I thought I would try to put a bead of caulk around between base of unit and roof. this was suggested in a thread on forum. but I am leery of using anything like sikaflex 221 because if this does not work I will have unit pulled and resealed. therefor I do not want it permanently glued to roof. looking for suggestions for a caulk that will create a permanent bond but will hold up to heat and uv

[idroba]

I can only advise you that doing it right the first time is easier. You need a new AC gasket. To put one on requires pulling the AC unit up and replacing the gasket with a new one. Anything else will just cause you more grief in the long run.

[Rich W]

Originally Posted by idroba

I can only advise you that doing it right the first time is easier. You need a new AC gasket. To put one on requires pulling the AC unit up and replacing the gasket with a new one. Anything else will just cause you more grief in the long run.

That's what I've heard, replace the gasket, never caulk or you're going from bad to worse.

[lewster]

Ditto! NONE of the makers of RV air units recommend any sealants when mounting new roof units.

Do it right............ Do it once!!

You will need a new gasket for the bottom of the A/C base pan and depending on the year of your trailer, a second gasket that is contained in Dometic's aux. drain kit.

Besides, any sealant that could be easily removed is not worth the purchase price!!!!


Lew Farber
RVIA/RVDA Nationally Certified Master Tech
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center
Lifeline Batteries**Magnum Inverters
541-490-6357

[wrbaron]

thanks everyone, I was trying to do it on the cheap, but I will listen to voice of experience here.

[Siegmann]

Lewster, the base of my AC base/pan is fully caulked to the roof surface, and came that way from the factory. Has Airstream changed the mounting method since '98?

[lewster]

Originally Posted by Siegmann

Lewster, the base of my AC base/pan is fully caulked to the roof surface, and came that way from the factory. Has Airstream changed the mounting method since '98?

Absolutely! Airstream finally joined the rest of the RV world (almost) n
by ditching the drain pan and using Dometic's Aux. drain kit. No sealant to the roof!!!!

Only problem is Airstream orders their Dometic units without the bottom gasket, just like on your installation. The drain kit should have TWO GASKETS to seal and work properly.

You can try to fix yours with more SikaFlex, as they used grey 221 for yours initially, or you can upgrade the entire mounting the way it is meant to be done as designed by Dometic.

PM me for more info if you are interested in the latter. 😁


Lew Farber
RVIA/RVDA Nationally Certified Master Tech
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center
Lifeline Batteries**Magnum Inverters
541-490-6357

[Siegmann]

Lewster, thanks, but no leaks to date. I'll keep your offer in mind if things should change.

[wrbaron]

Lewster,, I originally started this thread, I have a 2005 19" and I have a small leak at front of airconditioner drips down thru louvers, I can see the sikaflex where it squeezed out on the roof underneath ac unit so how do I add more as you suggest? do I just caulk around the perimeter gap? so if this is not possible, is adding the gasket a do it yourself option? if not should this be done only at airstream dealer or repair shop? thanks

[lewster]

Originally Posted by wrbaron

Lewster,, I originally started this thread, I have a 2005 19" and I have a small leak at front of airconditioner drips down thru louvers, I can see the sikaflex where it squeezed out on the roof underneath ac unit so how do I add more as you suggest? do I just caulk around the perimeter gap? so if this is not possible, is adding the gasket a do it yourself option? if not should this be done only at airstream dealer or repair shop? thanks

If adding more SikaFlex, it should be done from the outside, but there's no room between the A/C base pan and the roof to facilitate that. I had an '06 19 CCD and removed the entire base pan and did the dual gasket replacement.

I don't know if a dealer will be savvy to this as Airstream STILL only uses a single gasket. You could do it yourself but will require a bit of scraping once you remove the upper A/C unit.


Lew Farber
RVIA/RVDA Nationally Certified Master Tech
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center
Lifeline Batteries**Magnum Inverters
541-490-6357