Best use of roof top space?

R

rod utterback

New member
Apr 27, 2016
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Hello All,

I have spent most of this year reconditioning my ’73 Canyonlands (26 ft.) and am currently working on the roof configuration. Since I haven’t actually camped in this vehicle I need advice. Will dual roof a/c be required for summer camping in the southwest? It appears that there isn’t enough roof room for dual a/c and a storage pod. I assume that dual a/c front mounted is not a good idea and the vehicle is not pre wired for such. Originally I planned on a Fantastic fan mounted in the front-most 14 x 14, then the original dometic a/c, followed by a second a/c in the rear 14 x 14 and the standard cargo pod with railing.

Is one high btu unit available? Where is the best location for the fan? Is the storage pod a good idea? What is the best all round configuration? I really wanted the storage.

Everyone has been most helpful so far, so I thought I’d ask. Thanks.

Rod Utterback
1973 Canyonlands 26ft.
Escondido, Ca.
 
Ours had two AC's middle and rear. When we got it there was a pod between the AC's. As our dash air is dead we replaced the AC's with new ones
mounted front and rear. On our '74 it was not a problem to fish the nonmetallic cable from the front position into the cabinets over the kitchen and
then into the electrical compartment.

Have both the front and middle AC/vent openings open and the ceiling will flex down enough to fish the wire through.
--
Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
 
You could always rig up a https://www.highseer.com/inverter-ductless-cassette.html for heat and cool.
--
Bill Van Vlack
'76 Royale; Guemes Island, Washington; Twin bed, full (DS) side bath, Brazilian Redwood counter and settee tops,455, 6KW generator; new owner a/o mid
November 2015; Since arrival: New HVAC blower, heat flap cable, headlight switch.
 
I ran power to the front opening. Since roof ac's intake in the front and blow air rearward, mounting as far forward as possible helps to have cool
air in the front of the coach. Some units can be mounted either direction. If so, orienting the rear unit so that it intakes air in the rear and blows
forward helps in getting the cool air where you want it instead of having it bounce off the rear glass or having it loose air flow by having to make a
180 degree turn in the inside cover assembly.
--
John Sharpe
Humble, TX
78 Eleganza II
 
I have the larger Atwood unit in the front-most opening on my 73.
It does an excellent job of cooling everything forward of the side bath.
This was at the coast of North Carolina at the end of August, high 90's every day.
It kept the rear semi cool.
If you sat in front of the hallway opening, it was pretty cold.
But it did not do a great job of circulating cool air past that point.
Add a sunburn to the day and it was not cool enough at all.

Right now, we have MaxxAir vent covers over the middle and rear openings.
I have Yakima round bars mounted in between and a Yakima SpaceCase will fit up there.
It is a long narrow case.
I plan to add the smaller Atwood unit to the rear next spring, and hope the SpaceCase still fits.
If it does not, I will look for a shorter wider unit.
--
1973 GMC 26' Glacier - Unknown Mileage - Has a new switch pitch transmission with Powerdrive
 
My new used 26' has two Fantastics, one in the bathroom, one center front. Two A/Cs, mid and rear. They will pull the interior fro 100+ to
comfortable in less than ten minutes. The single unit in the 23' is marginal on a blacktop lot in Atlanta july sun. Holds ~~ 80. Once the sun drops
a bit, it's plenty.

--johnny
--
'76 23' transmode Norris upfit, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.

"Sometimes I wonder what tomorrow's gonna bring when I think about my dirty life and times" --Warren Zevon
 
My 15.5btu atwood A/C in the front area, pushes alot of cool air. However without other changes in the coach, I think you will struggle to keep
cool.

with that said, I personally feel if a person tints the window with the proper heat reflecting tint, and add some insulation, I bet you could keep
it cool with the one high BTU A/C in front. But I have not tested that yet.

I am not sure of your roof configuration, my palm beach front to back, is a 14x14 fantastic fan, then a atwood A/C unit, behind that is my storage
pod, and in the rear 14x14 hole is an original duotherm A/C unit.

--
Jon Roche
75 palm beach
St. Cloud, MN
http://lqqkatjon.blogspot.com/
 
My 26' has a sideways pod and no railing... dangerous.
The 23' has a front to back pod and railings, much safer.

--johnny
--
'76 23' transmode Norris upfit, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.

"Sometimes I wonder what tomorrow's gonna bring when I think about my dirty life and times" --Warren Zevon
 
> A tempting idea, but did you notice that those are all designed for 230 vac
> operation, making them incompatible with all GMC OEM Onans?
>
> Ken H.

I found a couple 120V units while googling, but I think it's a little too early for these to be applied to an RV. Given their popularity in Europe,
along with energy costs and smaller RVs, I would expect them to be available in a few years. The present outdoor unit design is not really suited for
our coaches; maybe when a roof-mounted design becomes available. It's probably possible to mount the ceiling cassette or a fan-coil unit somewhere
unobtrusive. If you could close couple a roof mounted outdoor unit to a fan-coil unit in a compartment it might work. Routing refer lines from the
roof to the indoor unit is also problematic.

--
Bill Van Vlack
'76 Royale; Guemes Island, Washington; Twin bed, full (DS) side bath, Brazilian Redwood counter and settee tops,455, 6KW generator; new owner a/o mid
November 2015; Since arrival: New HVAC blower, heat flap cable, headlight switch.
 
Ours came with 2 AC units (mid and back), the roof pod (it's not centered,
it's shifted towards the drivers side slightly) and has the railing. There
is also a fantastic fan in the front. I ended up taking the pod off right
away because half the bolts holding it down are stripped. I haven't
researched the best way to reattach it yet.

On Tue, Oct 18, 2016 at 11:44 AM Bill Van Vlack
wrote:

> > A tempting idea, but did you notice that those are all designed for 230
> vac
> > operation, making them incompatible with all GMC OEM Onans?
> >
> > Ken H.
>
>
> I found a couple 120V units while googling, but I think it's a little too
> early for these to be applied to an RV. Given their popularity in Europe,
> along with energy costs and smaller RVs, I would expect them to be
> available in a few years. The present outdoor unit design is not really
> suited for
> our coaches; maybe when a roof-mounted design becomes available. It's
> probably possible to mount the ceiling cassette or a fan-coil unit somewhere
> unobtrusive. If you could close couple a roof mounted outdoor unit to a
> fan-coil unit in a compartment it might work. Routing refer lines from the
> roof to the indoor unit is also problematic.
>
> --
> Bill Van Vlack
> '76 Royale; Guemes Island, Washington; Twin bed, full (DS) side bath,
> Brazilian Redwood counter and settee tops,455, 6KW generator; new owner a/o
> mid
> November 2015; Since arrival: New HVAC blower, heat flap cable, headlight
> switch.
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
My '78 Royale has two A/C units, two Fantastic Fans, and a rooftop pod (as well as a medium-size solar panel on top of the front A/C unit). Yeah,
it's snug up there, but there's really no down side to the configuration that I can think of... other than a little bit of a hit to my gas mileage
dragging all that stuff through the atmosphere.

FWIW, one A/C should be enough to keep the coach cool at night, but starting with the coach in the sun on a 110° day in Arizona, you really DO need
two units to get the interior cooled down quickly.

--
Mark Hickey
Mesa, AZ
1978 Royale Center Kitchen
 
Our coach has two original Duotherm units, one mid and one rear, with a pod in between. We don't camp all that often in the summer, except at higher
elevations where it is considerably cooler, but when we do, we need both those AC units to keep cool. It is also nice to be able to turn the mid unit
off and just use the rear unit sometimes to reduce the noise.

The pod doesn't have much in it, mostly light things, but it is reinforced to hold a 140 watt solar panel on top. I have recently added a 55 watt
panel on top of the rear AC unit as well.

http://www.gmcmhphotos.com/photos/solar-battery-charging/p46407-140-watt-kyocera-panel.html

http://www.gmcmhphotos.com/photos/solar-battery-charging/p60920-expanding-the-system.html
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging
 
I have 4 AC units, Dash, Aux under the couch, two roof air, Penguin 13.5 Roof airs, Limo tinted windows, Extra insulation.
No storage pod, no ladder. I use a receiver hitch carrier if I need to carry more than I have storage for, which is almost never now that the kids are gone.

----------------------------------------

>
> My '78 Royale has two A/C units, two Fantastic Fans, and a rooftop pod (as well as a medium-size solar panel on top of the front A/C unit). Yeah,
> it's snug up there, but there's really no down side to the configuration that I can think of... other than a little bit of a hit to my gas mileage
> dragging all that stuff through the atmosphere.
>
> FWIW, one A/C should be enough to keep the coach cool at night, but starting with the coach in the sun on a 110° day in Arizona, you really DO need
> two units to get the interior cooled down quickly.
>
> --
> Mark Hickey
> Mesa, AZ
> 1978 Royale Center Kitchen
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
> I have 4 AC units, Dash, Aux under the couch, two roof air, Penguin 13.5 Roof airs, Limo tinted windows, Extra insulation.
> No storage pod, no ladder. I use a receiver hitch carrier if I need to carry more than I have storage for, which is almost never now that the kids
> are gone.

Hello Keith.

I'm interested to know more about your under couch "aux" unit.
Any info you can share would be greatly appreciated!

[the worst day working on my GMC is better than the best day at work]
--
David del Rio
Raymond, CA
75 Avion
 
I used a rear unit out of a conversion van, then Teed it off the cabin compressor.
I paid an AC shop to make the Tee and the lines, I charged it with Duracool. I used a fan control out of a 90's Dodge Caravan to run the fan.
The unit has provisions for heat too, but I didn't plumb that, it's a summer coach.

Under my couch is packed, the furnace, Aux AC and a big subwoffer take up all the space under there.
There might be an easier way, but I like junk yard parts whenever possible.

----------------------------------------

>

>> I have 4 AC units, Dash, Aux under the couch, two roof air, Penguin 13.5 Roof airs, Limo tinted windows, Extra insulation.
>> No storage pod, no ladder. I use a receiver hitch carrier if I need to carry more than I have storage for, which is almost never now that the kids
>> are gone.
>
>
> Hello Keith.
>
> I'm interested to know more about your under couch "aux" unit.
> Any info you can share would be greatly appreciated!
>
> [the worst day working on my GMC is better than the best day at work]
> --
> David del Rio
> Raymond, CA
> 75 Avion
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
On the subject of Mini Splits being 230 vac.

Seeing that Helen and I are almost off grid I pay quite a bit of attention to this subject.

Notice that they are inverter driven variable DC motors.

Some folks are bypassing the companies inverter and using DC from solar panels.
There are actually some systems that are manufactured to run on a solar panel with 110vac backup.
The thing that is very interesting about these is the inside unit is not as big as GMC overhead cabinets which has been a draw back.
I saw one install that the outside unit was where we put our spare tire, and the inside unit was where we sometimes put a "Gun cabinet" across the
rear.

https://www.highseer.com/inverter-ductless-cassette.html
--
Monte in Okla
76 Birchaven 23
77 Eleganza 26 (under complete restoration)
 
> On the subject of Mini Splits being 230 vac.
> Seeing that Helen and I are almost off grid I pay quite a bit of attention to this subject.
>
> Notice that they are inverter driven variable DC motors.
>
> Some folks are bypassing the companies inverter and using DC from solar panels.
> There are actually some systems that are manufactured to run on a solar panel with 110vac backup.
> The thing that is very interesting about these is the inside unit is not as big as GMC overhead cabinets which has been a draw back.
> I saw one install that the outside unit was where we put our spare tire, and the inside unit was where we sometimes put a "Gun cabinet" across the
> rear.
>
> https://www.highseer.com/inverter-ductless-cassette.html
OK. You got my attention. How do you bypass the company's inverter (converter) and run it off DC?
--
73 23' Sequoia 4 Sale
73 23' CanyonLands Parts Unit 4 Sale
Upper Alabama
"Highest price does not guarantee highest quality."
 
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