It seems like it’s about a thousand degrees in most parts of the country right now. So if you’re like me, you’re thinking of any way possible to squeeze a little more performance out of your RV’s air conditioner. One gadget that promises an average of 40% improvement is from RV Airflow Systems. This product works only for ducted RV air conditioning systems – and we have one. So I installed one in our Winnebago EKKO, and took before and after measurements of the airflow to check it out.
TL;DR: Yes, the RV Airflow Systems product did increase the airflow from our air conditioner. But in our EKKO, the changes were insignificant, and nowhere near the claimed 40%. Save your money, and save your time. Based on our testing, simply taping over the cold air dump in your RV’s air conditioner will get you the vast majority of the benefits of this product. You don’t need to spend time making styrofoam insulation teepees like you see all over YouTube, either. Just 10 minutes and half a roll of tape will get you most of the way there.
A Few Caveats, First
The first thing I want to point out about the RV Airflow System you see in the video, is that this was a factory customized unit. You see, RV Airflow Systems are made to fit standard RV air conditioners within a standard set of dimensions. The roof opening and vent locations in our Winnebago EKKO did not meet this set of parameters. But if you call the factory and provide them dimensions, they will customize a unit to fit your opening. I thought that was pretty cool – they’ll do it for anyone… no charge! So it is possible that in a more standard RV roof opening, that the performance of the RV Airflow System might be better.
The next thing you should know is that we paid straight-up retail for our RV Airflow unit.
And the third – and probably biggest – thing you should know is that our “before” numbers were not from a stock air conditioner setup, but rather from an improved setup. We had previously installed the RV AC Silencer (trying to make the air conditioner quieter). Part of that install includes taping over the cold air dump that’s right below the fan in the air conditioner. This alone seemed to get us most of the improved performance that the RV Airflow System claims.
The Tests
I don’t want to just repeat what’s in the video. The tests are super easy, and you should be able to replicate them to see what kind of airflow you’re getting out of your current setup. But people will probably want links to two things that I used to make the measurements.
The first is this anemometer. I don’t think you have to use this one exactly – there are a number of seemingly identical ones for sale, and I don’t have any reason to believe that one is better than the other. It’s only a $30 instrument, and I didn’t have a way to verify the absolute accuracy of the anemometer versus a laboratory standard. But one thing I did before proceeding with the video though was to repeat the same measurements on the same vents on different days at different times to at least verify the *consistency* of the meter. I was satisfied with that, so I went ahead with the test.
The second thing you might want is this funnel that I snapped onto the anemometer. I just printed it out of PLA. The opening on it is large enough to cover the whole of the vent openings in our RV. The inner opening (where the airflow enters the meter) is 66mm in diameter. When you do the math, that turns out to be a measurement area of 0.037 square feet. The anemometer will give results in feet per minute, so the formula to get cubic feet per minute is just:
0.037 sq ft X Airspeed (ft/min) = air flow in cfm
When I used the anemometer to take readings, I set it on its “average” setting. In this mode, the anemometer displays the trailing average for the last 15 seconds of readings. This made it easy to capture the data, instead of trying to guess second-to-second peaks. I just waited until the average stopped changing.
My Mod to the Mod
As it turned out, my mod with the parabolic ramps and whatnot didn’t improve the situation much. I did succeed in reducing the airflow to the Nordic Blast over my bed, but improvements to the airflow in other parts of the coach were limited to single digit percentages. I guess it’s better, and I’m leaving it in for now. But if I knew then what I know now, I wouldn’t have bothered. Based on that, I deleted the model for the parabolic ramps, so I won’t be tempted to waste any more time with it. 
The Data
If you want to take a look at the data for yourself, I’ve uploaded it, and you can download it here:
RV Airflow Test Data
One other thing I should mention: The sound levels in the RV with and without the RV Airflow (with or without my mod) were exactly the same. No change in noise levels on either low or high speed.
So What Do I Recommend?
Well, first, remember that this approach only works for ducted RV air conditioning systems. If you’ve got an air conditioner with a single-location air distribution box, then none of this applies to you.
Next – before you buy any product for your air conditioner, and before you start cutting sheets of styrofoam to fit inside your plenum, try the super cheap and easy approach. Simply get some foil tape, and tape over the cold air dump at the floor of your air conditioner’s plenum. Seal up any other gaps or sources of air leakage you find while you’re in there. See if that ten minutes and half a roll of tape improves your performance enough to make you happy. I’m guessing it will.
In our Winnebago EKKO, simply taping this over with foil improved the airflow so much, that there wasn’t much left for the RV Airflow System to improve. Now granted, your RV and your duct system may be different from ours. The tape might not work as well in other RVs, but it’s so easy and so cheap, that it’s at least worth a shot.
That should just about do it for this one. I’m sure there will be comments and questions, so leave them down below.
Stay cool, everyone!