Before RV Airflow released their insert for the Furrion A/C, I created a simple insert to help direct more air into the forward ducts.

First picture shows the air outlet of the Furrion. The ducts connect on the left and right of the plenum in this picture.

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I cut a piece of corrugated plastic to fit into the foam outlet and then widen to fill the plenum. I cut it to a snug fit and then tested in various positions until I was happy with the increased flow. I then secured using foil tape.

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I am very happy with the increased airflow to the forward ducts and that I am still able to use the air "dump" when we want to rapidly cool the main living space. (Also pretty happy with the cost.)

As has been mentioned in a number of posts, I also took the opportunity to snug the A/C mounting bolts ("snug" being the key word here) and close any gaps in the transition to the ducts.