[BigBoy2U]

Since I been working on my furnace one thing seems to bother me a lot. In my old Avion the furnace was in a compartment that was sealed off from the other areas of the underbelly and was only able to draw return air into the furnace from inside the coach. It had a return under a cabinet. If you wanted you could make a filter to fit in this area. On my 05 MS I noticted the blower sits in the housing for the furnace and its open to the underbelly area. It draws in from the underbelly and I guess it might pull "some" interior air from the cabin. But I noticed the hot air output to be much much less than my 35K BTU Atwood in my Avion. It would put out really HOT air...the Suburban in the MS puts out warm air. So I have concluded that the blower is drawing cool air from the underbelly and not really drawing much from the cabin causing a much higher rise to occur. Not to mention all the road dust, mouse crap and whatever is floating around in the under belly is being blown into the cabin. So a few questions. 1. Has anyone sealed off that area to create a better flow from furnace to cabin and back? 2. Has anyone taken a thermal temp of the heat output of the vents in the cabin to give me an idea of how hot the air is? 3. Has anyone made a filter to fit over the end of the blower intake to filter the air into the cabin? I think there is a so called filter above the pocket door. But it really doent filter much since the pocket door is open and the access panel to the electric is open along with the underbelly. My point is the furnace doesnt really draw much air back into the furnace from the cabin. Seems it draws more from the belly area than anything. Why would you want to move unfilterd air from the belly area into the cabin? Sorry I was just really suprised to see how poorly this was constructed. To have the furnace sitting in the belly area and pulling air from that area into the cabin. I just dont find it healthy when you store stuff that is dirty, road dirt and dust and critter crap along the smells of any chemicals, holding tank and whatever else is in that area. If you left the non sealing slidding door to the access open then your also pulling in all the air from the storage area. There must be a better way to do this?