Roof AC opinons

DetroitDan

DetroitDan

New member
Mar 28, 2017
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Just looking for experience.

I will be in mostly moderate climes, but could get to hot areas sometimes.

The current configuration from front to back: Vent/fan; AC; AC

I am going to replace the fan(s) and AC(s), and trying decide which way to go (front to back):

AC; Vent/fan; AC

or

Vent/fan; AC; Vent/Fan

or

AC; Vent/fan; Vent/fan.

Experienced opinions will be helpful.
--
Dan Wallace
Detroit Metro
1974 Canyon Lands 260
Headers, 3.55, 16"
Floor plan 26-9
 
Well, I have vent/AC/AC. I would weigh your coach and see if you want more weight forward or not. That said with only 1 AC I would go center hole.
I run with only dash air driving as I like fresh air coming in not 100% recirculated.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
My recommendation would be A/C front, Maxfan or Fantastic fan middle, A/C rear. This would allow you to run the forward mounted A/C while on the road
and the dash air is not up to the task. This would be ideal down here in the Deep South.
Depending upon your choices, if you are replacing everything up top, I would consider 15000 btu up front and 13500btu in the rear. But this might be
overkill in a more moderate area.
Tom, who had vent, A/C, A/C.
--
2012 Phoenix Cruiser model 2552
KA4CSG
 
Interesting idea. Maybe I'll run power to the front vent while I had the
head liner down. just in case.

> My recommendation would be A/C front, Maxfan or Fantastic fan middle, A/C
> rear. This would allow you to run the forward mounted A/C while on the road
> and the dash air is not up to the task. This would be ideal down here in
> the Deep South.
> Depending upon your choices, if you are replacing everything up top, I
> would consider 15000 btu up front and 13500btu in the rear. But this might
> be
> overkill in a more moderate area.
> Tom, who had vent, A/C, A/C.
> --
> 2012 Phoenix Cruiser model 2552
> KA4CSG
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>
 
If I had the headliner down, I think running 120 and 12 to each opening would allow future flexibility with HVAC, venting, and lighting.
--
Dan Wallace
Detroit Metro
1974 Canyon Lands 260
Headers, 3.55, 16"
Floor plan 26-9
 
We are currently running vent/AC/exhaust fan. Like you we spend most of our time in a moderate climate in NH and are currently traveling in warm climates. We’ve used mostly the cross draft of the vans and a cracked window to cool the inside down mostly. The central ac works great and cools down the whole cabin pretty quick. If you were traveling mostly in southern states I’d say 2 ACs to keep cool all the time. But conserving weight and moving it in front of the rear wheels helps even if it’s just a little bit. Just my .02.
JimD
Sent from my iPhone

>
> If I had the headliner down, I think running 120 and 12 to each opening would allow future flexibility with HVAC, venting, and lighting.
> --
> Dan Wallace
> Detroit Metro
> 1974 Canyon Lands 260
> Headers, 3.55, 16"
> Floor plan 26-9
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Dan,

As long as you are shopping, Keep the option of 15K open. You have the electrics onboard to handle it, and frequently there is only a small
difference in price. Do not worry about the unit being to big, most have working thermostats. So, too big is as frequent an issue as left over
lobster.

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
Dan,
I'm running AC-vent/fan-AC down here in Houston. What I did wrong was to go with two 15,000 btu AC's. I should of gone with a 15,000 btu up front and
a 11,000 btu unit in the rear. The 15,000 btu in the rear constantly short cycles because of the small area it cools.
But realistically I only run one AC at a time, even on the hottest days. And I am a firm believer in the Atwood air conditioners.

You might want to run wire to all openings since you have the ceiling out. Then run a 15,000 up front, and vent/fans to the rest. Try that
configuration for a season, and add a smaller unit in the rear if needed.

Scott.
--
Scott Nutter
1978 Royale Center Kitchen, Patterson 455, switch pitch tranny, 3.21 final drive, Quad bags, tankless water heater, everything Lenzi.
Houston, Texas
 
Also study the discharge pattern of the AC unit you are considering. The OEM DuoTherms had a foreward/rearward pattern with a selectable diverter
door. These had a very high exit velocity so my large front unit has no problem making it to the front windshield from the midships position.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
The days of the "good stuff" are behind us now. Heavy duty stuff that
lasted longer than most modern marriages have gone the way of the do-do
bird or passenger pigeons. Manufacturers figured out they could increase
return sales if they just cheapen stuff up a bit, cut a corner here and
there, etc. I bought a GE gas range when I remodeled my home kitchen.
Supposed to be stainless steel, and porcelain burner trays, cast iron pot
holders. Well, a few years in, the stainless turned out to be brushed
something other than, coated with plastic coating that was not heat proof.
Can't scrub it with scotch brite. Looks like crap. Same with the porcelain?
stuff. Blisters and chips off. New parts available? You guess where they
are made. Not in the USA.
VIKING or Wolf or Sub Zero it ain't.
Jim Hupy
Salem, Or

On Sat, Mar 24, 2018, 8:03 AM John R. Lebetski
wrote:

> Also study the discharge pattern of the AC unit you are considering. The
> OEM DuoTherms had a foreward/rearward pattern with a selectable diverter
> door. These had a very high exit velocity so my large front unit has no
> problem making it to the front windshield from the midships position.
> --
> John Lebetski
> Woodstock, IL
> 77 Eleganza II
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Recently - it’s been easy to point the finger of blame at the country of origin for quality issues, when in reality it’s the parent company that dictates precisely how a particular product is manufactured. In your case - GE is to blame, not the contract manufacturer...

GE stock holders and GE customers are *really* the drivers... The consumer has been enjoying the race to the bottom, but not always happy when they get there!

Rob
Victoria, BC
76 Royale - Rear Twins/Dry Bath

>
> The days of the "good stuff" are behind us now. Heavy duty stuff that
> lasted longer than most modern marriages have gone the way of the do-do
> bird or passenger pigeons. Manufacturers figured out they could increase
> return sales if they just cheapen stuff up a bit, cut a corner here and
> there, etc. I bought a GE gas range when I remodeled my home kitchen.
> Supposed to be stainless steel, and porcelain burner trays, cast iron pot
> holders. Well, a few years in, the stainless turned out to be brushed
> something other than, coated with plastic coating that was not heat proof.
> Can't scrub it with scotch brite. Looks like crap. Same with the porcelain?
> stuff. Blisters and chips off. New parts available? You guess where they
> are made. Not in the USA.
> VIKING or Wolf or Sub Zero it ain't.
> Jim Hupy
> Salem, Or
 
We agree with Scott, but Bob says he'd go ahead and put both units in at
the same time--a 15k up front and 11k in the back, especially if you're
going to travel in the warmer climates. He says, "Why wait and have to go
back in to put the second one in?". When we bought our two 15k units, the
price was only about $100 each more than the 11k units.

Sandra

> Dan,
> I'm running AC-vent/fan-AC down here in Houston. What I did wrong was to
> go with two 15,000 btu AC's. I should of gone with a 15,000 btu up front and
> a 11,000 btu unit in the rear. The 15,000 btu in the rear constantly
> short cycles because of the small area it cools.
> But realistically I only run one AC at a time, even on the hottest days.
> And I am a firm believer in the Atwood air conditioners.
>
> You might want to run wire to all openings since you have the ceiling out.
> Then run a 15,000 up front, and vent/fans to the rest. Try that
> configuration for a season, and add a smaller unit in the rear if needed.
>
> Scott.
> --
> Scott Nutter
> 1978 Royale Center Kitchen, Patterson 455, switch pitch tranny, 3.21 final
> drive, Quad bags, tankless water heater, everything Lenzi.
> Houston, Texas
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Addressing the quality aspect of products built today brings to mind an episode that happened years ago to a good friend.
My friend had/has a business that builds generators that were primarily for RV's and had built his reputation on his quality products. I've seen some
of his gensets with over 35,000 hours on them that were still running and producing electricity. Anyway, Onan approached him about building a diesel
generator for them (this was before they built one themselves) to be used in an RV. His proposal for a genset with estimates of longevity
requirements he required for his units far exceeded Onans desires. They wanted a unit that would 'require' repair after the warranty expired to keep
their dealers happy. After building the reputation over years, my friend wasn't about to furnish a product to Onan that would tarnish it. That was the
primary reason no deal was struck.
So, it's not really where the parts are built, rather how demanding the client is on QC.
Hal
--
1977 Royale 101348,

1977 Royale 101586, Diesel powered,

1975 Eleganza II, 101230,

1974 Eagle Bus 45',w/slideout,

Rio Rancho, NM
 
G'day,

IIRC 15 up front and 11 down the back is what GMC installed from the factory, I reckon those guys knew what they were doing.

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808
 
Rob
I don’t think they made a 15,000 btu unit at that time.
My original factory unit was a 13,500 btu.

Emery Stora

>
> G'day,
>
> IIRC 15 up front and 11 down the back is what GMC installed from the factory, I reckon those guys knew what they were doing.
>
> Regards,
> Rob M.
> The Pedantic Mechanic
> Sydney, Australia
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
> USA '77 Kingsley - TZE 267V100808
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Emery,

Oops - you're right, its 6:00 am here in Sydney and I haven't had my morning coffee yet! :-)

I've got two 13.5's in Double Trouble.

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces] On Behalf Of Emery Stora
Sent: Sunday, March 25, 2018 5:57 AM
To: gmclist
Subject: Re: [GMCnet] Roof AC opinons

Rob
I don’t think they made a 15,000 btu unit at that time.
My original factory unit was a 13,500 btu.

Emery Stora

>
> G'day,
>
> IIRC 15 up front and 11 down the back is what GMC installed from the factory, I reckon those guys knew what they were doing.
>
> Regards,
> Rob M.
> The Pedantic Mechanic
> Sydney, Australia
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
> USA '77 Kingsley - TZE 267V100808
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
The 'Dancing Bear' ('75 Eleganza we bought over 20 years ago) has 2 ACs, front and middle, with a Fantastic Fan in the rear. I thought it was
strange, but once I corrected the wiring (no, you CAN'T run 2 ACs on one circuit) it works well. When it's REALLY hot, you need all the AC you can get
in the living area. We almost never run the AC at night, and when/if we did, we wouldn't want it droning right over our heads while we try to sleep.
Having both units toward the front allows either to direct cold air to the cockpit if necessary. And having two units provides a backup just in case
one of those 44 year old Duo-Therms acts up.
HTH
Rick Staples
--
Rick Staples, '75 Eleganza, Johnstown, CO

"Advice is a dangerous gift, even from the Wise to the Wise, and all paths may run ill." -Tolkien
 
Another option for the REAR AC.....
If a person wanted to go low profile and stay at 11,000 btu's Or less(because of short cycling with the higher btu units). One could go with the
Coleman Mach unit at 9,000 btu's. Since the rear area is so small, I would think the 9,000 btu unit would be almost ideal..but then it should
definitely be paired with a 15,000 btu unit up front..at least in theory......anyone running this configuration??
Scott
--
Scott Nutter
1978 Royale Center Kitchen, Patterson 455, switch pitch tranny, 3.21 final drive, Quad bags, tankless water heater, everything Lenzi.
Houston, Texas
 
Thank you all for the shared knowledge!

I have some inquiries out on new units...
--
Dan Wallace
Detroit Metro
1974 Canyon Lands 260
Headers, 3.55, 16"
Floor plan 26-9
 
Thanks again for your opinions/experiences with A/Cs and vents!

Today I ordered an Atwood 15025 + 15021 for the middle hole. (13.5K very high-efficiency with remote)

If we find that we are roasting a lot, we'll order another for the back.

For each of the front and back holes I ordered a MaxxFan 4000k and MaxxAir II rain cover. (manual up, 10-speed w/ thermostat)

I also ordered an open box Flo-Jet portable macerator pump, because the price seemed good ($150)

Trying want to hit the ground running and complete the roof stuff as soon as I retrieve The Chief from the storage warehouse.

Next weekend hoping to get the ground cloth and rails in place for the gravel pad in my backyard, so we can legally keep it at home.

This is fun now! Never before have I put more money into a non-necessity than I could sell it for ... but, like my family said, "You're 60 now ... "
--
Dan Wallace
Detroit Metro
1974 Canyon Lands 260
Headers, 3.55, 16"
Floor plan 26-9
 
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