Hello Rod,
Low Flow:
We just got done plugging over sized holes and insulating pipes in the RV basement. When we pulled down the rearbasement wall we found that the air supply to the two forward ducts comes through two 4" circular flexible ducts that link them to the main furnace duct. There are two 90ΒΊ bends in these flexible ducts, that is sure to slow the air flow way down. Solid / smooth sided dusts would help or a matching rectangular fabricated duct, but I am too old and fat to spend that much time in that basement.
Since the front of the 5th wheel is higher I figure that the hot air from the back will migrate forward.
By the way, there are huge holes for pipes and wires that run from the basement to the kitchen cabinets and to the underbelly. Any critters that find their way into the underbelly or basement have easy access to the interior of the RV. I used a package of steel wool and a can of great-stuff and 5 feet of gorilla tape to slow them down.
Best of luck to you on your travels.
Noisy Furnace:
We just had our furnace serviced. The fan impeller was touchingits housing. The intake/ exhaust holes through the RV did not line up with the furnace. This caused the entire furnace housingto be twisted; they also adjusted the impeller on the fan motor shaft. It is quite quiet now.
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