New Montana3720RL 5th wheel ac leaking

[mewlake]

Just bought our 2017 Montana3720RL 5th wheel in July. On our maiden voyage the Dometic Whisper quiet ac in the living room area was leaking out of the ducted intake vents whenever the unit cycled off with the fan in auto or in rainstorms. We phoned the dealership from the campground and they didn't understand what we were saying(they thought it was the ac with the inside ceiling shroud)so we phoned Dometic and they suggested it was a faulty install, a faulty unit or a cracked drain pan and to run the fan on high to help dry up water until we could get it serviced. We took it in for service to the dealership and picked it up last week. they tapped something up and refitted the gasket. We went camping this last weekend and the ac is still leaking. We have to keep a pot under the intake vents to catch the water.We have made another service appointment to take the trailer in after our next trip. Anyone else having this trouble? how did the service centre fix it for you?

[Rondo]

Rob contact the Keystone Customer Service and tell them your problem. They will start a file on your unit and also tell them about your experience with your dealer. They may give you another dealer to contact if you are not happy with your dealer. Since it is a new unit, it should be covered under warranty. I have heard of some units that have had the drain holes plugged by muddobers and also others that have not been installed correctly with the slope of the unit not being correct. Definitely call the Keystone Customer Service and get a file started.

[1retired06]

Dealer questionable. Leak is likely bad seal/gasket installation the roof or blocked drain holes. Is there a another likely cause? Maybe but betting one of those two.

[phillyg]

Our 2016 3711FL is in the dealership for a rain leak that comes out of the rear AC return vents, right over our bed and the television. The service tech told me he's seen a few already and it has to do with an improper install.

[navybanker]

Had the same problem first trip and dealer said when it's hot humid leave fan on high. That has worked so far.

[RVokie]

Ours had the same issue. It presented itself during the PDI, which was a good thing. They ended up either enlarging the existing drain holes, or added additional ones. Whatever the solution, it appears to have fixed it.

[mewlake]

We have another appointment for repairs next week. in the mean time I brought the trailer home in prep for another trip. I turned the AC on and it was running when I left to go to the store. I went back in the trailer after a couple of hours to see how cool it was and the AC was off. I checked the Tstat and it was dead, nothing on the screen and would not turn on. The tstat has 5 volts going to the back of it but I can't find the what the Tstat voltage should be. I am hoping they can fix it on Monday as we are going away again, hopefully. I also had a look in the return air vent for the AC and there was some standing water in it PLUS the return vent in the ceiling is collapsed at both sides. I can hardly get my finger in there. The original size of the vent looks to be about 2H x 6W. With the intake vent collapsed the AC will not be working efficiently.

[mewlake]

Also I just saw another 2017 model that was built later than ours and the intake vents are a lot larger than ours. Dealer just called and the trailer is going in today.(Saturday)

[jameswbarton]

Wow,
So if yours was leaking out of the intake vents was it condensation due to the supply air/ return air baffle out of position creating a dew point in the duct and the moisture caused the collapse?

Please let us know what caused it!

[mewlake]

When the AC unit is in auto mode and cycles off some of the water makes it inside the intake vent and drips inside the trailer, some drains onto the roof. I am starting to find fixes out there for this, one TSB from Dometic for Forest River, https://dealers.forestriverinc.com/d...OMETIC-TSB.pdf and there was a similar one from Heartland.
We were told from Dometic to run the unit on high all the time until it is fixed. This solves the problem while it is running but if we turn the AC off it will leak inside also.
FYI, Dometic was quicker to respond to my e-mail than Keystone so far.

[jameswbarton]

Ah, so in some of the Dometic Forest river instals they did not meet Dometic Spes and are having to retrofit more vents and air return. So I wonder if Keystone will ever do that as it has the same issue. So far all Keystone told me is my unit is working correctly. Even with the starved airflow they will not admit.

[mewlake]

This is a new system and as more and more trailers will have it installed there will be more complaints. But until then we will have to fight to make it right. I have seen similar TSB's for Heartland trailers who is owned by Thor industries, who also owns Keystone.

[jameswbarton]

I wonder how many years to get Keystone to make it right. It looks like the whisper quiet system came out in January 2015. Plenty of performance issues reported on the internet and blogs. Keystone has many complaints on them and Forest River is already fixing them with recall. I somehow do not think Keystone is going to call a whoops and fix the airflow issue like Forest River and Heartland are doing. If it was in the works I am sure I would have heard about it from Keystone Owner Relations AC expert I have been talking with, trying to get mine up to specification.

[jlb27537]

Back in 2001 I bought a new floorplan Newmar 5th. I had a problem of water dripping out of the air intake vents. Seems like the new floor plan caused the elimination of both 2 intake and 2 exhaust vents in the ceiling. Basically the A/C was starving for air on the intake side and the head pressure on the exhaust side was too high.

The fix was to install 2 extra intakes and and 2 extra supply outlets

Like Dometic suggested, improper installation.