We just purchased a Winnebago 30T and are wondering how the basement is heated. Our 5th wheel had a heat duct in the basement but the salesman said our Vista didn't have a heat duct. How does it stay warm?
Most Winnebagos have a duct into the basement. I believe your Vista has individual compartments for basement storage and I'm sure don't have any ducts to them. The water tank and pump though probably do have a duct or return air passing through the compartment.
The "duct" in my coach is simply an open heater hose that empties into the enclosed area where the water tanks, dump valves, etc are located. You will never see it without partially dismanteling the water service bay. It provides direct heat from one of my two lp furnaces, but I am not sure which!
There is also indirect heat via airways/wireways/plumbingways under cabinets, etc.