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Improving dometic air output

December 07, 2023, 07:38:50 pm

It's that time of year where I'm looking for things to keep me occupied when I can't get out on the boat.

Been bothered by how little output I get from my overhead ducts when running the AC.  I strictly use the ducts and shut off the main opening under the ac unit.

Using plexiglass I made a more efficient ram/duct inside the space between the cover and the ac unit.  Bit of a prototype and still needs sound proofing but this improved the output by 5x.

Next I will cut out the sheet metal divider between the output and intake to create more space.  I will also experiment with sound proofing the top of the grill with the exception of the filter area.
 
 The intake fan makes a lot of noise so I turned the grill 180 degrees so the filter is now on the opposite side of the intake. Similar design to the $250 noise reduction grills. 

It may be a wash with the noise in the end but I can tell you for sure you won't have to listen to it nearly as long with volume I'm getting out of the ducts.

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Re: Improving dometic air output

Reply #1 – December 07, 2023, 10:47:00 pm

Reading your post I remember there was a company that produced vent air flow mods for the AC units.  Does anyone know the company or the post thermo were mentioned in?

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Re: Improving dometic air output

Reply #2 – December 08, 2023, 01:03:09 am

Pretty sure it's on YouTube. Type in RV vent mod

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Re: Improving dometic air output

Reply #3 – December 08, 2023, 06:40:22 am

There are two products that I know of. RV airflow makes one that addresses the output and wacko addresses the silencing of the return.

So if you get them both your laying out $400 x 2 units.

I'm trying to go on the cheap but at the same time I want the ability to make changes to optimize.

I installed the wacko on a friend's dometic and it really did reduce the noise.  It protrudes a couple inches from the ceiling which creates space for the return air to flow without so much air related noise.

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Re: Improving dometic air output

Reply #4 – December 09, 2023, 10:36:43 am

Did something very similar to our AC units, smoothed the airflow into the ducts, closed off the direct down vent.
It amazed me our much BETTER the air flowed, you can actually feel it up front now when driving.
Better air flow and less noise all with done with materials just laying around.

Turning the intake 180 degrees, didn't think of that.

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