Honestly, I did a little project on this. Took apart the furnace cover and taped all the blanks not in use. Also, sealed up the register's correctly. In the pass-thru, I used metal register tape and re-did some sloppy openings. There are two feeding lines to the front and I shortened them and taped them and re-installed the hiding panel.
These all helped out to elimiate waste. Really, you don't want the full furnace flow to go into the bedroom, it would become a sauna.
2013 Jayco Eagle 334RBTS
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