Dometic Penguin Drain Kit

[lewster]

GOOD-BYE DRAIN PAN!


After several requests, I have included a few recent photos of the actual installation of the Dometic Auxiliary Drain Kit # 3107668.016 that I installed while changing a couple of 10 year old Penguin I 13.5K models to new Penguin II 15K heat pump units.

The first shot is the original gasket, cut to allow the tubing from the drain cups (which have been screwed into the base pan) to pass thru. The cuts are then completely sealed with SikaFlex 221 polyurethane sealant.

Second shot is after installation of the second gasket directly on top of the original. This allows for the needed clearance after installation of the drain cups.

Third is the additional spacer blocks required to be installed at the back of the base pan to maintain a flat, solid installation on your roof. The white 'T' connector seen in the first photo is then plugged into your internal drain line.

Once you screw the unit down to the roof by compressing the gaskets to 50% of their original thickness, you have a clean, tight, waterproof roof seal. Be sure to blow out the trailer's drain line first to be sure that it is free of obstructions.

[lewster]

And I almost forgot. You can get the drip kit from any Dometic dealer.

[Lance M]

Awesome! Thanks Lewster.

[cwf]

Did those extra gaskets and spacers come with drain kit?

[lewster]

Originally Posted by cwf

Did those extra gaskets and spacers come with drain kit?

Everything you need for the installation is included in the box (even instructions). You use the sealant of your choice........BUT NO SILICONE!

Oh, the air conditioner is extra.................

[KJRitchie]

Do you have any photos of units that had the drain pan and were converted? What prevents condensation coming out the two holes on drain pan units on existing installed units? On my 2008 vintage Dometic 13.5K the area between the evaporator intake and the blower output is where the drain pan is attached. On your photos above the whole bottom of the AC seems to be covered with a one piece plate with openings for the air intake and output only. Does AS cut out the part between under the evaporator to install the drip pan. Surely they don't.

I'm still confused how this will work on an existing Penquin with drain pan.

If you have no photos please explain what is done to remove the drain pan and install this new system. To me you'd have to order the whole bottom plate in addition to the drain kit to do the conversion to have your current AC look like the one in your photos.

Any chance you can post larger photos?
Thanks

Kelvin

[lewster]

Originally Posted by KJRitchie

Do you have any photos of units that had the drain pan and were converted? What prevents condensation coming out the two holes on drain pan units on existing installed units? On my 2008 vintage Dometic 13.5K the area between the evaporator intake and the blower output is where the drain pan is attached. On your photos above the whole bottom of the AC seems to be covered with a one piece plate with openings for the air intake and output only. Does AS cut out the part between under the evaporator to install the drip pan. Surely they don't.

I'm still confused how this will work on an existing Penquin with drain pan.

If you have no photos please explain what is done to remove the drain pan and install this new system. To me you'd have to order the whole bottom plate in addition to the drain kit to do the conversion to have your current AC look like the one in your photos.

Any chance you can post larger photos?
Thanks

Kelvin

Sorry, but I don't have any shots of the Airstream-specific drain pan. You might be mis-understanding how this Dometic drain kit works.

If you want to use the Dometic drain kit, you have to remove the Airstream drain pan to reveal the bare aluminum of the roof. In fact, because the Airstream drain pan is glued to the roof, you have to literally cut it off and do a good bit of scraping to get the aluminum surrounding the 14 X 14 opening as clean as possible to allow a good seal from the new gaskets. In fact, if you remove your A/C unit from it's Airstream drain pan, you will notice that there is no foam gasket present, just a thin piece of double sided foam tape to join the A/C to the drain pan.

The bottom of the A/C unit in the photo IS the base pan of the unit. Typically, in a normal installation on any other type of RV, the base gasket of the A/C sits directly on the roof and gets clamped to the roof from the mounting frame underneath the unit found on the inside at the ceiling. Four 1/4-20 X 6" bolts do the compressing of the gasket to form the seal to the roof. The lower return air grill or air distribution box (depending on what you have for temperature control) will have an internal metal separation gate that segregates the warmer return (intake) air from the cooler exhaust coming from the evaporator.

The second gasket used with the drain kit allows for the additional clearance of the drain cups that is required to let the cups clear the roof. The reasons that the Dometic drain kit works better than the Airstream drain pan are:

• there is no bottom pan to overflow condensate into the coach if the drain line gets kinked or blocked
• any excess condensate will overflow the drain cups that are located outside the A/C unit and find it's exit on the roof, not inside the trailer.

Any other questions or confusion?

[Crusty]

And don't install the cups to the unit with any sealer. They're made so that if the drain line fills with water for any reason the water will overflow out the top of the cups and onto the outside of the trailer.

The cups are a much better solution than the old pan with drain rig.

[perryg114]

I have the same setup on my Briskair and it sorta kinda works. I don't know if the bottom pan is the same as the Penquin or not but my pan has holes that don't need to be there that bypass the cups. There is a channel that catches condensate from the compressor lines but that channel has a hole in it. I need to put some silver duct tape over that hole and see how it does then. The double gaskets have to be retorqued ever so often until both gaskets fully compress. The system works but it could be better than it is with a little work.

Perry

[lewster]

Originally Posted by perryg114

I have the same setup on my Briskair and it sorta kinda works. I don't know if the bottom pan is the same as the Penquin or not but my pan has holes that don't need to be there that bypass the cups. There is a channel that catches condensate from the compressor lines but that channel has a hole in it. I need to put some silver duct tape over that hole and see how it does then. The double gaskets have to be retorqued ever so often until both gaskets fully compress. The system works but it could be better than it is with a little work.

Perry

When properly installing a Dometic unit with the drain kit, you tighten the retaining bolts to compress the gaskets to 50% of their original thickness. Since these are 1" gaskets and you now have 2 of them, there should be a 1" total gap between the roof and the A/C unit.

There is no re-torquind required if installed properly, as over compressing these gaskets has the potential to cause them to leak.

[perryg114]

I tightened mine till the unit sat level and no more and this was a gradual process.

Perry

[KJRitchie]

Originally Posted by lewster

Sorry, but I don't have any shots of the Airstream-specific drain pan. You might be mis-understanding how this Dometic drain kit works.

If you want to use the Dometic drain kit, you have to remove the Airstream drain pan to reveal the bare aluminum of the roof. In fact, because the Airstream drain pan is glued to the roof, you have to literally cut it off and do a good bit of scraping to get the aluminum surrounding the 14 X 14 opening as clean as possible to allow a good seal from the new gaskets. In fact, if you remove your A/C unit from it's Airstream drain pan, you will notice that there is no foam gasket present, just a thin piece of double sided foam tape to join the A/C to the drain pan.

Ok, I think I'm getting it. My AC still drips through the side holes like in your photos except there is a pan the directs it to the drain pan sump I can see from inside the trailer then out the drain tube.

How much labor time is calculated for this job to switch over to the new drain system? If I explain what I need to have done to an Airstream dealer or repair shop will I get a blank stare? Is this a common job now?

Thanks

Kelvin

[lewster]

Originally Posted by KJRitchie

Ok, I think I'm getting it. My AC still drips through the side holes like in your photos except there is a pan the directs it to the drain pan sump I can see from inside the trailer then out the drain tube.

How much labor time is calculated for this job to switch over to the new drain system? If I explain what I need to have done to an Airstream dealer or repair shop will I get a blank stare? Is this a common job now?

Thanks

Kelvin

I did 2 Airstreams (25FB's) for the local KOA a couple of months ago when the roof A/C units puked out. IIRC, it took me 2 hours each. I might expect a bit more time from a tech who hash't ever removed the bonded on base pan from a roof yet, but that is about what it takes me to do them.

And as always...YMMV!

[A W Warn]

Originally Posted by KJRitchie

Do you have any photos of units that had the drain pan and were converted? What prevents condensation coming out the two holes on drain pan units on existing installed units? On my 2008 vintage Dometic 13.5K the area between the evaporator intake and the blower output is where the drain pan is attached. On your photos above the whole bottom of the AC seems to be covered with a one piece plate with openings for the air intake and output only. Does AS cut out the part between under the evaporator to install the drip pan. Surely they don't.

I'm still confused how this will work on an existing Penquin with drain pan.

If you have no photos please explain what is done to remove the drain pan and install this new system. To me you'd have to order the whole bottom plate in addition to the drain kit to do the conversion to have your current AC look like the one in your photos.

Any chance you can post larger photos?
Thanks

Kelvin

Lewster,

I think this photo shows what Kevin is talking about. (A photo of the original pan that came on my Safari, replaced it 2 years ago) The condensate from above drips into that trough that runs through the center of the roof opening. I do not see how the new system would work with my existing Dometic Penguin AC unit (model 600312.321). How does it collect the condensate from the coils and direct it into the drain tube?

[lewster]

Every Dometic roof A/C had a drain area built into the base pan where it collects the condensate from the evaporator coils. There is a drain hole in the base pan on either side of this section where the condensate normally drains onto the roof. The drain cups are positioned directly under these drain holes to catch the condensate and channel it thru the included tubing of the drain kit, where it joins to the internal drain hose of the Airstream and gets channeled out under the belly ban.

You have to remove the plastic drain pan that Airstream provides and because your unit has no 14 X 14 gasket, one must be added to the bottom of the A/C base pan. You then add the second gasket (used to raise the unit to allow clearance between the roof and the drain cups included with the drain kit to complete the installation.

[A W Warn]

Thanks for explaining. I misunderstood your first post when you said base pan, I was thinking the plastic one, not the bottom of the AC. I did not turn my AC unit onto the side (thinking about compressor oil getting into coils) so that I could see the bottom. I did not realize the condensate comes through two holes in the base of the AC unit.

So those two white objects outside of the gaskets are the drain cups, small basins that collect the condensate. Makes perfect sense! If I ever do that again, I will not use the original Airstream pan.

edit add:
1. Do the hold down bolts require retightening as the gaskets age?
2. How is the original drain pipe connected to the cups?

[lewster]

Originally Posted by A W Warn

Thanks for explaining. I misunderstood your first post when you said base pan, I was thinking the plastic one, not the bottom of the AC. I did not turn my AC unit onto the side (thinking about compressor oil getting into coils) so that I could see the bottom. I did not realize the condensate comes through two holes in the base of the AC unit.

So those two white objects outside of the gaskets are the drain cups, small basins that collect the condensate. Makes perfect sense! If I ever do that again, I will not use the original Airstream pan.

edit add:
1. Do the hold down bolts require retightening as the gaskets age?
2. How is the original drain pipe connected to the cups?

The cups have 1/2" nipples molded to them that the included tubing connects to and is retained with pressure clamps. Once the gasket is tightened to 50% of its original thickness, you generally never re-torque them unless the bolt positions have changed. Be careful not to over-tighten the bolts and compress the gasket more than 50% of its original depth.

[Steve Bryant]

I'm about ready to rework the drain pan on my '91 trailer with the AS pan or the Dometic cups. Lew has been very patient with me to explain how the Dometic twin drain cup system works and I have done extensive searches and carefully read the posts. Two things that still concern me are:

1. A while back I talked to AS customer service and they said that for a Penguin, the factory drain pan worked better. They said that although the factory at Jackson Center now installs the Dometic cup system, it doesn't catch as much condensate and about half of the water drips down the drain tube and about half drips down the side of the trailer. Also, an Airstream dealer who sells and installs both parts (AS pan and Dometic Cups + 14" Gaskets) advises that they've had less complaints with the AS pan. I don't know what to think as I'm open to either method.

2. The second thing that I don't quite understand is the two inch thickness of the foam shims enough for an Airstream's curved roof? The instructions from Dometic are for a flat roofed trailer. Do I need to do anything extra to compensate for the radius of the AS roof. It looks like the long piece of foam tape supporting the aft end of the AC unit under the condenser coils would probably be thick enough since it is at the top of the roof curve in the center. However the shorter piece of 2X2 foam that goes under the compressor might need to be thicker since the roof is curving downward and the compressor is relatively heavy.



I know that I'm overthinking all of this, but I want to do the best thing, install it correctly once and be trouble-free for many years to come. I've had enough trouble with leaks.

I've ordered a replacement shroud and I have both drain pan and cups/gasket in my shopping cart at Out of Doors Mart and I'm ready to delete one and order the other. Any help will be appreciated

Thanks,

Steve

[Frank's Trailer Works]

Lewster, You saved my bacon again with this post! I installed one today and nowhere in the install directions did it mention the doubling up. I was concerned about crushing the tubes and why there was a second gasket. Monday, I will correct this.

[perryg114]

They are correct about half the condensate does run down the side of the trailer. There are some holes that don't need to be there.

Perry