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[GMCnet] Best use of roof top space? [message #308939] Mon, 17 October 2016 20:12 Go to next message
<diego.hotrod is currently offline  <diego.hotrod   United States
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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.

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Re: [GMCnet] Best use of roof top space? [message #308943 is a reply to message #308939] Mon, 17 October 2016 20:29 Go to previous messageGo to next message
midlf is currently offline  midlf   United States
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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
Re: [GMCnet] Best use of roof top space? [message #308961 is a reply to message #308943] Tue, 18 October 2016 00:28 Go to previous messageGo to next message
Bill Van Vlack is currently offline  Bill Van Vlack   United States
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You could always rig up a ceiling cassette mini-split 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.
Re: [GMCnet] Best use of roof top space? [message #308966 is a reply to message #308961] Tue, 18 October 2016 04:43 Go to previous messageGo to next message
John  Sharpe is currently offline  John Sharpe   Canada
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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
Porter, TX
78 Eleganza II, TBI
40 Ford Panel, TPI
Re: [GMCnet] Best use of roof top space? [message #308967 is a reply to message #308961] Tue, 18 October 2016 06:07 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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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.

On Tue, Oct 18, 2016 at 1:28 AM, Bill Van Vlack
wrote:

> You could always rig up a https://www.highseer.com/
> inverter-ductless-cassette.html for heat and cool.
> --
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Best use of roof top space? [message #308968 is a reply to message #308939] Tue, 18 October 2016 07:49 Go to previous messageGo to next message
Michael Leipold is currently offline  Michael Leipold   United States
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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 Smile
Re: [GMCnet] Best use of roof top space? [message #308973 is a reply to message #308939] Tue, 18 October 2016 08:04 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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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


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: [GMCnet] Best use of roof top space? [message #308977 is a reply to message #308939] Tue, 18 October 2016 08:39 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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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 EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: [GMCnet] Best use of roof top space? [message #308983 is a reply to message #308939] Tue, 18 October 2016 09:45 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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My 26' has a sideways pod and no railing... dangerous.
The 23' has a front to back pod and railings, much safer.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: [GMCnet] Best use of roof top space? [message #308992 is a reply to message #308967] Tue, 18 October 2016 10:43 Go to previous messageGo to next message
Bill Van Vlack is currently offline  Bill Van Vlack   United States
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Ken Henderson wrote on Tue, 18 October 2016 06:07
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.
Re: [GMCnet] Best use of roof top space? [message #308994 is a reply to message #308992] Tue, 18 October 2016 11:06 Go to previous messageGo to next message
Ethan James is currently offline  Ethan James   United States
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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:

> Ken Henderson wrote on Tue, 18 October 2016 06:07
>> 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.
>
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>
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Re: [GMCnet] Best use of roof top space? [message #308997 is a reply to message #308939] Tue, 18 October 2016 11:30 Go to previous messageGo to next message
habbyguy is currently offline  habbyguy   United States
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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.
http://www.habcycles.com/GMC1.jpg


Mark Hickey Mesa, AZ 1978 Royale Center Kitchen
Re: [GMCnet] Best use of roof top space? [message #309000 is a reply to message #308939] Tue, 18 October 2016 11:58 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
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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. GMCSJ and GMCMI member
Re: [GMCnet] Best use of roof top space? [message #309004 is a reply to message #308997] Tue, 18 October 2016 12:24 Go to previous messageGo to next message
Keith V is currently offline  Keith V   United States
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Location: Mounds View,MN
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Senior Member
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
>
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Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
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Re: [GMCnet] Best use of roof top space? [message #309009 is a reply to message #309004] Tue, 18 October 2016 14:30 Go to previous messageGo to next message
David del Rio is currently offline  David del Rio   United States
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Keith V wrote on Tue, 18 October 2016 10:24
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 - 75 Avion - Raymond, CA
Re: [GMCnet] Best use of roof top space? [message #309042 is a reply to message #309009] Wed, 19 October 2016 11:36 Go to previous messageGo to next message
Keith V is currently offline  Keith V   United States
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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.

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

>
> Keith V wrote on Tue, 18 October 2016 10:24
>> 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
>
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Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
Re: [GMCnet] Best use of roof top space? [message #309046 is a reply to message #308967] Wed, 19 October 2016 13:48 Go to previous messageGo to next message
Monte Jestes is currently offline  Monte Jestes   United States
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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)
75 Eleganza 26 almost completely redone
Re: [GMCnet] Best use of roof top space? [message #309050 is a reply to message #309046] Wed, 19 October 2016 16:02 Go to previous message
A Hamilto is currently offline  A Hamilto   United States
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Monte Jestes wrote on Wed, 19 October 2016 13:48
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?
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