Resealing DRV A/C Dometic Penguin II Unit On Roof

[dmorse68]

Has anyone ever resealed or replaced their DRV Mobile Suites A/C unit on the roof? I think I have water intrusion at the A/C rooftop seal and would like to hear from people that know how its mounted to the roof and how to reseal it.

I've researched Youtube videos, but they all show interior mounting bolts that lie under an interior plastic shroud on the inside of the RV. However, DRV's don't have an interior shroud. They have a solid, padded head liner.

Are the mounting bolts for the AC unit under the main exterior cover of the Dometic Penguin II unit?

Thanks for your help
David

[TXiceman]

Cummins12V98 wrote:
"I then torqued all the lag bolts on all 3 to 50” pounds"

That's an interesting torque. Reality that's slightly above 4'# TQ.

You only want to compress the gasket, not crush it.

Ken

[Cummins12V98]

"I then torqued all the lag bolts on all 3 to 50” pounds"

That's an interesting torque. Reality that's slightly above 4'# TQ.

[Retired_JSO]

pcm1959 wrote:

dmorse68 wrote:

pcm1959 wrote:
Those lag bolts that hold a/c unit on to the roof on many of the new RVs with no visible means of attachment on the inside are a huge source of possible water as they are outside the a/c seal and/or shroud. Be SURE they are properly sealed.
Many a/c units are leaking into the roof on these types of a/c units unknow to the owner since it is not likely to show up on the inside due to the insulation and ceiling panel particularly if a vinyl/padded ceiling.

The only way I discovered I had water intrusion was, I took the bedroom’s fantastic fan inner shroud trim piece off so that I could place a mouse trap up in the insulation cavity, and saw the roof plywood dark and wet.

There ya go! Trust me, there are many, many others with the same situation and don't know it.

There are 3 units on my fifth wheel. After a heavy rain,I discovered a small drip of water at the most rear register actually behind where the a/c is mounted. Thought at first it was condensation. After another heavy rain, drip drip. I then torqued all the lag bolts on all 3 to 50” pounds which has stopped any visible leak.

[Cummins12V98]

This is why the lag bolts should be checked.

[pcm1959]

dmorse68 wrote:

pcm1959 wrote:
Those lag bolts that hold a/c unit on to the roof on many of the new RVs with no visible means of attachment on the inside are a huge source of possible water as they are outside the a/c seal and/or shroud. Be SURE they are properly sealed.
Many a/c units are leaking into the roof on these types of a/c units unknow to the owner since it is not likely to show up on the inside due to the insulation and ceiling panel particularly if a vinyl/padded ceiling.

The only way I discovered I had water intrusion was, I took the bedroom’s fantastic fan inner shroud trim piece off so that I could place a mouse trap up in the insulation cavity, and saw the roof plywood dark and wet.

There ya go! Trust me, there are many, many others with the same situation and don't know it.

[dmorse68]

pcm1959 wrote:
Those lag bolts that hold a/c unit on to the roof on many of the new RVs with no visible means of attachment on the inside are a huge source of possible water as they are outside the a/c seal and/or shroud. Be SURE they are properly sealed.
Many a/c units are leaking into the roof on these types of a/c units unknow to the owner since it is not likely to show up on the inside due to the insulation and ceiling panel particularly if a vinyl/padded ceiling.

The only way I discovered I had water intrusion was, I took the bedroom’s fantastic fan inner shroud trim piece off so that I could place a mouse trap up in the insulation cavity, and saw the roof plywood dark and wet.

[Cummins12V98]

I agree people should check tightness of lag bolts. I have owned 2 DRV's over 9 years with zero leaking. I am on DRV Forums with no leaks mentioned.

[stripit]

As a old auto body shop owner using 3M products always did waht they were designed to do and using the foam sealer tape I used was designed to stop water migation under a truck cap. Having one side of sticky it allowed the tape to seal to the unit and float on the roof top. The sealant dries and is not sticky once set so for the following 6 years of ownership of the DRV trailer and having no further leaks, I guess it worked as I had expected. If at the time the factory seal was available I would have purchased it, but where I was there was no seal. I did the next best thing and got the fix done. No big deal as I have learned a long time ago there may be more than one way to get the job done and have it work.

[pcm1959]

Those lag bolts that hold a/c unit on to the roof on many of the new RVs with no visible means of attachment on the inside are a huge source of possible water as they are outside the a/c seal and/or shroud. Be SURE they are properly sealed.
Many a/c units are leaking into the roof on these types of a/c units unknow to the owner since it is not likely to show up on the inside due to the insulation and ceiling panel particularly if a vinyl/padded ceiling.

[TXiceman]

Barney, our NitchHiker Champagne has the above the roof mounting system.

Ken

[BarneyS]

Thanks all for the clarification on the mounting on DRV units. Dang, 83 years old and still learn something everyday! 🙂
Barney

[TXiceman]

DO NOT us caulk of any sort on the A/C gasket. And yes, the higher end u nits are mounted from the outside with no inside access panel. It keeps then quieter than the through the roof units.

Get a proper replacement gasket and do not try to use a make shift gasket.

Ken

[Cummins12V98]

dmorse68 wrote:

Next time you try to remove the AC unit you WILL be pulling up your roof! Stick with proper gasket!

That makes sense. Thanks.

You R Welcome!

[dmorse68]

Next time you try to remove the AC unit you WILL be pulling up your roof! Stick with proper gasket!

That makes sense. Thanks.