collapsed a/c return ducts

[Mikendebbie]

The ducts are like a racetrack running full length of your rig like the screen shots show above. I doubt your ducts are 100% collapsed…for example from point A to point B in the screen shot below. They may be collapsed at a few points where registers were cut in. The idea of sticking some little pieces of PVC maybe 6” to 12” into the collapsed opening is to prop open and support the collapsed top side. I drew a bad sketch on the screen shot below.

[John Sigmone]

I was wondering if anybody can answer this question for me my rear AC unit on my Big Sky Montana 2017 is so loud we can barely sleep at night is this normal

[John Sigmone]

Thank you for the reply what I meant and maybe you misunderstood not the air conditioner vents but the return duct air vent

[Mikendebbie]

I could not find a pic of the ductwork in a 2014 model - but it has the racetrack duct system. The ductwork circles the AC units for the length of the coach. If you assume the AC support frame opening shown in my screen shot above is (say) 24”x24” - and assume the ductwork section is (say) 2”x14” - then you can measure the approximate distance from any vent in your ceiling to the main trunks of the racetrack duct system. I don’t know that branch ducts exist in the ceiling because you never see them in the factory tour videos. Even if you have a register in the ceiling that you think may be on a branch duct - use the assumptions I lay out to measure your approximate length. You won’t be measuring to the nearest millimeter - all you need to know is “it’s about YAY long”.

Frankly - you will only be able to insert short pieces of PVC into a collapsed section of ductwork thru the small vent or return opening.

The screen shot below demonstrates a duct collapse by squeezing a section. The collapse does not extend further down the duct section. I suppose a full collapse is possible - but not likely.

[Daryles]

While you are in the air return cavity, close up any gaps in the duct work. If you don't it sucks in hot air from the attic. Use AC foil tape. Clean the surface with alcohol first for good adhesion.
I could put three fingers through this gap.

[bshgto]

Originally Posted by John Sigmone

I was wondering if anybody can answer this question for me my rear AC unit on my Big Sky Montana 2017 is so loud we can barely sleep at night is this normal

LOL Only about 5000 posts on this subject. You`ll just have to get used to it. We actually like the white noise now drowns out road noise, airports, noisy neighbors and their dogs/kids.