Ducted roof top air

[TomC]

Nice job.  My next bus or motorhome will have a high enough ceiling to have a drop to facilitate ducting.  Am toying with the idea of using a Freightliner truck and making my own box-possibly a 26ft box that would facilitate a car inside and still be under 35ft overall.  Good Luck, TomC

[Nick Badame Refrig/ACC]

Nick do you have any pictures of your duct when your bus was being converted?

Hi Pat,

Yes, here are a couple..

Nick-

[TomC]

Nick- nice job!  You'd think from the pictures that you were a professional at air conditioning.  LOLO.  Good Luck, TomC

[DavidInWilmNC]

Nick, what type of insulation did you use for your ducts?  How thick is it?  Is it directly against the roof, or is there additional insulation between the roof and the duct?

Although my ceiling's not high enough for ducts in the center, there is hope!  When I installed my unit, I didn't cut the main beam but instead mounted to the side.  I've been thinking that if I used a ducted air box / return and ran the ducts to the side of the bus along the windows, I could achieve close to the same thing. I'd have to fabricate a surface 'box' that would be finished the same as the ceiling to take the place of the current free-blowing section that's there now.  This would have to connect to the side ducts on the ceiling (or slightly recessed), but this is over the sofa and won't be in the way.  The free-blowing part does hang down about 2.5", so I wouldn't lose any additional head room.  The side ducts could easily be integrated into a valance above the windows.  The vents would be mounted onto this valance.  My MC-8 still has the drop in the ceiling over the driver and steps.  If I mounted the front unit close enough, I should be able to run the ducts for the driver and passenger in the is space and still have a couple runs to the side channels.  My OTR air still works, so that's not a prime concern at this point, but it could be in the future.  At any rate, the bus needs more than one A/C unit up front to cool it off when it's been sitting in the sun.  Have others run any surface ducts along the ceiling or walls? 

David

[Nick Badame Refrig/ACC]

Thanks Tom,

Hi David,

I lined the entire ceiling of my bus with tek foil [fbbf], then constructed my main trunk in a "U" shape with 1"

flanges to attatch it to the ceiling. Then wrapped the trunk with 1 layer of FBBF. The trunk is 2 1/2" X 14".

Here is a link to simular as to what I use.

http://www.teksupply.com/farm/supplies/prod1;ts1_tekfoil_reflective_foil_insulation;956af1a4_100760.html

David, You plan sounds like it will work. Just give good thought as to where you place your supply grills.

Good Luck
Nick-

[RTS/Daytona]

the way I used the ULTR-DUCT is different then it would be used in a house

I have 2 x 4's running the length of my RTS BUS (remember RTS's have 6'8" ceilings THE FRAME RIBS) on both sides forming a "H" channel 3.5" deep x 10"  wide - I then scored and folded and taped the ULTRA-DUCT to fit in that channel and used following bends to eliminate any sharp Right angle bends

The ULTRA-DUCT is supported  on both sides by the 2 x 4's and on top by my first layer of 3/4" inch insulation board R-MAX foam used to bring the roof level with the RTS's ribs - the bottom is supported by the RV ceiling - That leaves 3.5" of  layered insulation board R-MAX for the rest of the roof.  Plus that  addition 3/4" foam to fill to the frame ribs + 3/4"  foam in the roof dimples

I got so much insulation in my RTS - it's like driving in a THERMOS BOTTLE

The ULTRA-DUCT seams are taped but - where the hell are they going to go if the tape loosen (which it hasn't)

Pete RTS/Daytona 

Just the way I did it - am I'm very very pleased with it

The way FEATHER-LITE and MILLENIUM did it was to simply lay the boxed / taped ULTRA-DUCT ducts on top of the ceiling truss in their MILLION DALLOR Prevosts - I believed they used straps and wire ties to prevent them from moving around.

[JackConrad]

We used the UltraDuct in our bus.  We happened to be near Lowell, Indiana and picked up the 4x8 sheets at their facilty (They will cut the sheets into 2'x4' pieces for shipping by UPS). They took us on a tour through their plant and also showed us how they pre-assemble duct components for the major S&S builders in the area. Ours has been in since '99 and no signs of failure. We did follow their instructions to the letter when building and installing the ducts.  Jack