Duct Diagram

BDove · 07-21-2021, 09:45 AM

Anyone have a diagram of the overhead AC ducting for 2021 Alpine 3700FL with two AC units?

**chuckster57** · 07-21-2021, 10:40 AM

Unless you see it in a sales brochure, your not going to find a schematic available to the public.

If your having air flow issues there are fixes depending on the style you have. Does your have 2 ceiling assemblies with the “dump” grill and return filter?

Javi · 07-21-2021, 11:22 AM

Quote:

Originally Posted by chuckster57

Unless you see it in a sales brochure, your not going to find a schematic available to the public.

If your having air flow issues there are fixes depending on the style you have. Does your have 2 ceiling assemblies with the “dump” grill and return filter?

Chuck, he has a 2021 Alpine so I'm thinking it's like my Avalanche and closed..

I re-taped both the living area and the bedroom intake/filter ducts and all the registers on mine before we replaced the bedroom A/C. When they pulled the A/C off the roof, the ducting was also poorly taped. So I paid them to pull the living room A/C and re-tape it also... As I said it made a huge difference in air flow and the upgrade to 15K in the bedroom is fantastic..

BDove · 07-22-2021, 03:32 AM

I do not have the ceiling assemblies. I have seen the fixes for those. I am assuming the ceiling panels will have to be removed to access the ducting and plenum. I will leave that to dealer and warranty.

Rkmarple · 07-22-2021, 06:31 AM

Quote:

Originally Posted by BDove

Anyone have a diagram of the overhead AC ducting for 2021 Alpine 3700FL with two AC units?

Just had my 2021 Alpine repaired.
NOTE TO ALL: Poor manufacturing problem as noted by Lewis RV in OKC By Keystone!
Too much Spray insulation under both AC plenums blocked return air flow.
Also, foam board insulation within top of return air duct sagging down restricting airflow. Dealer noted same issue on multiple units!
Dealer had to pull AC units and also remove inside ceiling panels to repair.
Result plenty of air flow and cooling from both units.
Inspection technique by me was an endoscope (Amazon) which allowed me to view ducts on my iPhone via Bluetooth.

If having low airflow on new Keystone units, better check.

BDove · 07-22-2021, 09:42 AM

Thanks Rkmarple! I will show the dealer this post when I take it in.

ChuckS · 07-22-2021, 12:48 PM

Typical of what is being seen under the new 2021 Alpine A/C units…

Images from a group I am in.. only way to fix is remove the A/c units and clean up the mess

Show to your dealer …this is what will be seen

Javi · 07-22-2021, 02:18 PM

Quote:

Originally Posted by ChuckS

Typical of what is being seen under the new 2021 Alpine A/C units…

Images from a group I am in.. only way to fix is remove the A/c units and clean up the mess

Show to your dealer …this is what will be seen

Avalanche as well...

BDove · 07-23-2021, 08:24 AM

Thanks, I will show them this. What a mess.

BDove · 07-23-2021, 08:29 AM

You would think the installers would notice that, or at least QC. Apparently QC is absent.

browntl2454 · 07-27-2021, 04:42 AM

We have our 2021 Montana High Country in for warrantee issues. We had been in Colorado for a week. The temperature was in the 80s, and we had both air conditioners operating, and they weren't cooling properly. The service tech called and told me that the returns were almost taped shut, and the ceiling vents holes weren't cut out big enough. I guess it was something that got passed QC.

BDove · 07-27-2021, 05:40 AM

Thanks. Yes my returns have zero airflow going back in. I looked in return duct, it is partially collapsed and not sure if it is sealed properly. Probably blocked in plenum as well.

takpak · 07-29-2021, 09:09 AM

After having our 2017 Montana all these years, I finally got into the discharge louvers. We have two 15K units, main and bed areas. First year, I checked and improved the return plenums with the PVC pipe method and made sure they were open and free flowing. This year, I finally got around to checking the discharge vents, and what a mess. Bad sealing, some holes not cut right, etc. Nothing really serious, but it all adds up. Took down each assembly, and cut about an inch off the louver "pipe" so it doesn't protrude into the ductwork. That helped. Then re-taped each and every hole so it doesn't just blow into the ceiling area. Found a couple of them that were pretty bad and misaligned. All back together now, and it does seem to have better airflow. We shall see, come a hot day.....or cool day when using the heat pump feature.

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