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[GMCnet] Engine driven roof top AC to replace Dash AC [message #321319] Sun, 30 July 2017 17:06 Go to next message
Thomas Pryor is currently offline  Thomas Pryor   United States
Messages: 143
Registered: January 2011
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Senior Member
George Butts Wrote: We all know the dash AC does only a marginal job to
cool the front and forget the entire coach.

George "I believe you" when you made the comment that dash AC is
marginal. However, the cooling system is plenty "large enough" (capacity)
to handle "most" of our demands properly maintained. I do not believe
hanging more hardware on your coach is the answer.

The real issue is the HVAC (Heating, Ventilation, Air Conditioning) box AIR
FLOW . The Harrison Division of GM designed the system with no apparent
thought to air flow velocity .......OR..........the GM Truck & Bus guys
said "give me something that will fit into this space"! So we got a system
that only pressurizes the HVAC box and ignores air velocity and direction.
Most of us are aware that the blower on a traditional furnace located in
the basement of a home has a centrifugal fan that pushes air up
through the heating and AC coils to the registers on the 1st and 2nd
floors. That is what is most efficient. It is a Laminar Air flow model
with little Air Flow turbulence. Many Owners think that we have this
model for dash AC in our Coaches.

That is untrue.

Just think if, 1) a centrifugal blower fan in our home basement was
turned upside down and pushed air toward the basement floor 1st
..............and 2) was then was ducted to the right or left into the
chamber that housed the heating and AC coils! THAT CREATES TWO TURBULENT
AIR FLOW EVENTS! That is exactly the strategy our coaches have
employed..........no matter what year it was built and what attempts by GM
employed to rescue the design.

I have only minor exposure to "marginal AC" when traveling 5000 miles to
the Rally in South Dakota from Florida in my 23B. Yea it Sucks! I
recently posted on the GM Photo site a Modification that DOES NOT require a
complete revision of the HVAC Box or any of the controls. It is a one day
project for some, most will say a week end. It requires one Purchased
part ........a double centrifugal fan assembly and the construction of a
small duct from the floor of the coach to the HVAC box. If the
Centrifugal fan is used from my posting, removing wires from the existing
HI, Med, and Lo resistors on the driver side of the HVAC box and extending
them to the new Centrifugal Double fan is a trivial task. We now can look
forward to Laminar, not Turbulent air flow

SEE:
http://www.gmcmhphotos.com/photos/i-need-more-air/p63443-a-hvac-blower-modification.html

HOW CAN I HELP?
--
Regards,

Tom Pryor
4188 Limerick Dr
Lake Wales, Fl 33859
Cell 248 470 9186

Living on a waterfront is not a matter of life or death. Its more
important than that.
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Re: [GMCnet] Engine driven roof top AC to replace Dash AC [message #321326 is a reply to message #321319] Sun, 30 July 2017 17:37 Go to previous messageGo to next message
rcjordan   United States
Messages: 1913
Registered: October 2012
Location: Elizabeth City, North Car...
Karma: 1
Senior Member
Bob Heller also says it's an airflow problem. His solution was to add ports & 2" flex ducts to the existing box and vent them into the cabin floorboard.

SOLD 77 Royale Coachmen Side Dry Bath
76 Birchaven Coachmen Side Wet Bath
76 Eleganza
Elizabeth City, NC
Re: [GMCnet] Engine driven roof top AC to replace Dash AC [message #321357 is a reply to message #321319] Sun, 30 July 2017 22:03 Go to previous messageGo to next message
George B. is currently offline  George B.   United States
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Registered: February 2012
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Thanks Tom, great write up and project. Not sure that I followed the complete concept though. For clarification, are you are using the existing ducts in the dash but doing away with the existing blower motor and fan. If so I have a 1973 which has different dash ducts from the one in the pictures. I assume your modification with work just as well for a 73? Also I assume it gives the same benefits for the heater and defrost.

George Butts Las Vegas Nevada 73 "Custom 26' Q" & 76 23' Birchaven 71 Honda 600 Coupe & 01 Tracker Toads
Re: [GMCnet] Engine driven roof top AC to replace Dash AC [message #321359 is a reply to message #321357] Sun, 30 July 2017 22:16 Go to previous messageGo to next message
johnd01 is currently offline  johnd01   United States
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Location: Sacrameot
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Are you saying you are getting close to the same amount of cooling from the
engine hardware as you would get from a roof unit running off the Onan
generator?

On Sun, Jul 30, 2017 at 8:03 PM, GEORGE BUTTS via Gmclist <
gmclist@list.gmcnet.org> wrote:

> Thanks Tom, great write up and project. Not sure that I followed the
> complete concept though. For clarification, are you are using the existing
> ducts in the dash but doing away with the existing blower motor and fan.
> If so I have a 1973 which has different dash ducts from the one in the
> pictures. I assume your modification with work just as well for a 73?
> Also I assume it gives the same benefits for the heater and defrost.
> --
> George Butts
> Las Vegas Nevada
> 73 "Custom 26' Q" & 76 23' Birchaven
> 71 Honda 600 Coupe & 01 Tracker Toads
>
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--

*John Phillips*
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Johnd01 John Phillips Avion A2600 TZE064V101164 Rancho Cordova, CA (Sacramento)
Re: [GMCnet] Engine driven roof top AC to replace Dash AC [message #321360 is a reply to message #321319] Sun, 30 July 2017 22:25 Go to previous messageGo to next message
Olly Schmidt is currently offline  Olly Schmidt   United States
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Location: Germany and Scottsville, ...
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Senior Member
Thomas,

> If the Centrifugal fan is used from my posting, removing wires from > the existing HI, Med, and Lo resistors on the driver side of the >
HVAC box and extending them to the new Centrifugal Double fan is a >
trivial task. We now can look forward to Laminar, not Turbulent air > flow
is the end result, that you no longer utilize the existing HVAC at all,
ie. direction of air flow for heating and/or windshield de-fogging, or
is this purely for making sure the A/C is providing the needed cooling
to the poor sweating cockpit inhabitants?
--

Best regards

Peer Oliver Schmidt
PGP Key ID: 0x83E1C2EA

'76a Eleganza II, CA
'73 Sequoia, VA


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Best regards

Olly Schmidt
PGP Key ID: 0x18a9 3a1f 4196 bf22
'76a Eleganza II, VA
'73 Sequoia, SH, Germany
Re: [GMCnet] Engine driven roof top AC to replace Dash AC [message #321368 is a reply to message #321360] Sun, 30 July 2017 23:36 Go to previous messageGo to next message
johnd01 is currently offline  johnd01   United States
Messages: 354
Registered: July 2017
Location: Sacrameot
Karma: -1
Senior Member
Is this mostly better air flow (as in vent) rather than real refrigeration
cooling?

On Sun, Jul 30, 2017 at 8:25 PM, Peer Oliver Schmidt GMC <
posde@theinternet.de> wrote:

> Thomas,
>
>> If the Centrifugal fan is used from my posting, removing wires from >
> the existing HI, Med, and Lo resistors on the driver side of the >
> HVAC box and extending them to the new Centrifugal Double fan is a >
> trivial task. We now can look forward to Laminar, not Turbulent air > flow
> is the end result, that you no longer utilize the existing HVAC at all,
> ie. direction of air flow for heating and/or windshield de-fogging, or
> is this purely for making sure the A/C is providing the needed cooling
> to the poor sweating cockpit inhabitants?
> --
>
> Best regards
>
> Peer Oliver Schmidt
> PGP Key ID: 0x83E1C2EA
>
> '76a Eleganza II, CA
> '73 Sequoia, VA
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
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--

*John Phillips*
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Johnd01 John Phillips Avion A2600 TZE064V101164 Rancho Cordova, CA (Sacramento)
Re: [GMCnet] Engine driven roof top AC to replace Dash AC [message #321409 is a reply to message #321319] Mon, 31 July 2017 10:31 Go to previous messageGo to next message
Thomas Pryor is currently offline  Thomas Pryor   United States
Messages: 143
Registered: January 2011
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Senior Member
SO OKAY,

GEORGE B. The duct work changes made by GM on early coaches were mostly
to redirect what little air came out of the HVAC box and where the air came
from, inside or outside. This modification that I am employing does not
affect air management when it leaves the HVAC box..............the attempt
is to create more directional air velocity and laminar flow as air moves
through the HVAC box into what ever ventilating system you have. Yes it
does do away with the existing motor and centrifugal fan and all the HVAC
box inlets are abandoned. You will always use 100% recirculating air.
Some the GM modifications used only outside air and no recirculation
choice.

As I thought more about this change, it occurred to me that we could
use the original OEM motor/fan housing and refit it to the floor with a
single duct to the bottom of the HVAC Box. No new parts and just add wire
to reach the new location of the Motor and Fan, EH?



Peer Oliver Schmidt,

Yes we keep existing HVAC box, all the ventilation ducting and vacuum
actuators, as well as controls in the dash. Closing all under hood inlet
air openings from the old arrangement now eliminates heat created by the
engine and radiator to be ingested into the box. The only downside to this
modification is that you will no longer have access to outside air. When
you select "Vent" only on your dash, you won't get anything because that
feature is blocked off.




is the end result, that you no longer utilize the existing HVAC at all,
ie. direction of air flow for heating and/or windshield de-fogging, or
is this purely for making sure the A/C is providing the needed cooling
to the poor sweating cockpit inhabitants?
--
Regards,

Tom Pryor
4188 Limerick Dr
Lake Wales, Fl 33859
Cell 248 470 9186

Living on a waterfront is not a matter of life or death. Its more
important than that.
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Re: [GMCnet] Engine driven roof top AC to replace Dash AC [message #321417 is a reply to message #321319] Mon, 31 July 2017 10:59 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Registered: October 2010
Location: St. Cloud, MN
Karma: 5
Senior Member
tom,

any pictures of the completed floor unit? Is there a reason you were not able to just blow directly into the re-circulation duct at the bottom of the dash? I am just curious how much space this takes up, as my 75, there is limited space in that area to allow the engine lid to open up.

I was thinking the other day, about what it would take to add a sucker fan at the center dash outlets of my 75, when i seen your post on this.


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] Engine driven roof top AC to replace Dash AC [message #321426 is a reply to message #321319] Mon, 31 July 2017 11:50 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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Registered: May 2011
Location: Braselton ga
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Senior Member
This is on my list of 'sometime' mods, which I will probably address next time I get roasted on a summer trip.

Additionally, although this will solve the driver/front passenger cooling concern, I'm investigating some sort of air handler for the rest of the coach. According to an article in Hemmings, the A-6 compressor is capable of 27,000 BTU at 2000 RPM, improving to over 40,000 at 4K. This at 240PSI outlet pressure. Easily enough to keep the interior of the coach cool when traveling. I'm thinking a roof mounted condenser a la flatfront Econoline vans from the 60s and a couple of evaporator/fan units strategically placed, and some plumbing.


--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] Engine driven roof top AC to replace Dash AC [message #321428 is a reply to message #321417] Mon, 31 July 2017 12:09 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Registered: October 2010
Location: St. Cloud, MN
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Senior Member
lqqkatjon wrote on Mon, 31 July 2017 10:59
tom,

any pictures of the completed floor unit? Is there a reason you were not able to just blow directly into the re-circulation duct at the bottom of the dash? I am just curious how much space this takes up, as my 75, there is limited space in that area to allow the engine lid to open up.

I was thinking the other day, about what it would take to add a sucker fan at the center dash outlets of my 75, when i seen your post on this.




OK- I finally got to look at Tom's pictures closely and not on my phone. I see he does not have the re-circulation duct that I can tell in his pictures, that I have on my 75. On my 75 there is like a 2" tall x 14" long opening into the HVAC system right center bottom of dash that is the air source for the re-circulation(from what I remember and can tell). I am going to look a little closer and do some experimenting on my ducts. The final answer is to add an aux evaporator, but possibly adding this sort of fan to really force air through the existing system may work well, and be something very quick, easy and inexpensive to do.



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] Engine driven roof top AC to replace Dash AC [message #321430 is a reply to message #321319] Mon, 31 July 2017 12:15 Go to previous messageGo to next message
SeanKidd is currently offline  SeanKidd   United States
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The two auxiliary evaporators I installed are published at 17k btu, so double is 34k, plus the original Harrison, I'm running frosty cool and still froze one of the evaporators. Although I had planned on installing a parallel flow condenser to compensate for additional load, it was a little to big and didn't fit between frame rails. So I know the serpentine condenser is still up to the task. My last trip to Massachusetts in 90 degree weather was comfortable. I did add clear shower curtains, which I may need to get to Dillard,GA in a couple weeks. Seems traveling south, the sun beating in the windshield is difficult to avoid, and may overpower my triple evaporators.

Sean and Stephanie
73 Ex-CanyonLands 26' #317 "Oliver"
Hubler 1-Ton, Quad-Bags, Rear Disc, Reaction Arms, P.Huber TBs, 3.70:1 LSD Honda 6500 inverter gen.
Colonial Travelers
Re: [GMCnet] Engine driven roof top AC to replace Dash AC [message #321431 is a reply to message #321319] Mon, 31 July 2017 12:15 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Used to have a flower shop, and the dash air in the vans was inadequate for
floral delivery. E-150 fords. Solved this by tapping into the dash air
compressor and running refrigerant lines to the rear of the van to a
vintage air a/c unit suspended from the van roof inside the cargo area. It
would freeze your butt off on the hottest days. The flowers loved it, too.
I wouldn't be too keen on anything that interfered with access to the
engine hatch on a GMC. Too much vital stuff under there that needs to be
looked at on a regular basis. Maintenence on a coach is not a seldom
activity. I work on coaches that I know have not been looked at under the
hatch in months because of all the crap piled up on the hatch.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

On Jul 31, 2017 9:51 AM, "Johnny Bridges via Gmclist" <
gmclist@list.gmcnet.org> wrote:

This is on my list of 'sometime' mods, which I will probably address next
time I get roasted on a summer trip.

Additionally, although this will solve the driver/front passenger cooling
concern, I'm investigating some sort of air handler for the rest of the
coach. According to an article in Hemmings, the A-6 compressor is capable
of 27,000 BTU at 2000 RPM, improving to over 40,000 at 4K. This at 240PSI
outlet pressure. Easily enough to keep the interior of the coach cool when
traveling. I'm thinking a roof mounted condenser a la flatfront Econoline
vans from the 60s and a couple of evaporator/fan units strategically
placed, and some plumbing.


--johnny
--
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" - ol Andy, paraphrased


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Re: [GMCnet] Engine driven roof top AC to replace Dash AC [message #321433 is a reply to message #321430] Mon, 31 July 2017 13:00 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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You probably have a bigger problem with humidity than you have with
temperature. That would account for the icing. We in the west have high
temperature and low humidity. Icing is usually not a problem out here. Cure
for high humidity is greater airflow across the coils along with greater
cooling capacity. Glad I don't live in that part of the country. Supposed
to be near 100 degrees here today, 105 later in the week. When it gets over
90 in the shop, it is downright uncomfortable.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

On Jul 31, 2017 10:16 AM, "Sean Kidd" wrote:

> The two auxiliary evaporators I installed are published at 17k btu, so
> double is 34k, plus the original Harrison, I'm running frosty cool and still
> froze one of the evaporators. Although I had planned on installing a
> parallel flow condenser to compensate for additional load, it was a little
> to
> big and didn't fit between frame rails. So I know the serpentine
> condenser is still up to the task. My last trip to Massachusetts in 90
> degree
> weather was comfortable. I did add clear shower curtains, which I may
> need to get to Dillard,GA in a couple weeks. Seems traveling south, the sun
> beating in the windshield is difficult to avoid, and may overpower my
> triple evaporators.
> --
> Sean and Stephanie
> 73 Ex-CanyonLands 26' #317 "Oliver"
> Hubler 1-Ton, Quad-Bags, Rear Disc, Reaction Arms, P.Huber TBs, 3.70:1 LSD
> Honda 6500 inverter gen.
>
> Colonial Travelers
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>
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Re: [GMCnet] Engine driven roof top AC to replace Dash AC [message #321441 is a reply to message #321431] Mon, 31 July 2017 15:05 Go to previous messageGo to next message
Jim Galbavy is currently offline  Jim Galbavy   
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Registered: August 2007
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Senior Member
JimH, What you described is what JimB did to the dash air on my '73 x-CL. Tee'd
in an under dash vintage air type unit to my existing dash a/c 14 years ago and like you
said "will freeze your butt off". Only problem I've had in all this time is I've had to
add one can of R-12.

Works for me here in Florida.

jim Galbavy
'73 x-CL (ANNIE)
Lake Mary, FL
Re: [GMCnet] Engine driven roof top AC to replace Dash AC [message #321461 is a reply to message #321319] Mon, 31 July 2017 20:02 Go to previous messageGo to next message
Thomas Pryor is currently offline  Thomas Pryor   United States
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Registered: January 2011
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Senior Member
As Johnny Bridges stated the output of our A6 Compressor is an impressive
26000 BTU at 2000 RPM. We are just not able to distribute it efficiently
and effectively, just say'n. I have a new vintage air unit that I can
place under living area furniture if required. Don't plan to plumb it in.

Some have said that the modification will block the engine hatch
access...........no it won't. See: http://www.gmcmhphotos
.com/photos/i-need-more-air/p63452-f-img-09691.html

Also some comments that the return air duct is not shown in my images.
Again looking at the same image the firewall recirculating opening is shown
but not blocked off yet. That will be completed when I reinstall the IP.
http://www.gmcmhphotos.com/photos/i-need-more-air/p63452-f-img-09691.html

ALSO, IMHO ducting air thru the recirculating vent will only create more
turbulent air flow and not solve the air management problem.......The air
flow must come from lower quadrant and behind the HVAC
Box.......................KISS! knuff said.


Regards,

Tom Pryor
4188 Limerick Dr
Lake Wales, Fl 33859
Cell 248 470 9186

Living on a waterfront is not a matter of life or death. Its more
important than that.
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Re: [GMCnet] Engine driven roof top AC to replace Dash AC [message #321486 is a reply to message #321319] Tue, 01 August 2017 12:31 Go to previous messageGo to next message
TR 1 is currently offline  TR 1   United States
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Registered: August 2015
Location: DFW
Karma: -7
Senior Member
2 Comments:

Keep in mind, the A6 output quotes are at compressor rpm, not necessarily engine rpm. Not sure if the compressor is underdriven or overdriven, but I believe it is overdriven.

As for the heat through the windshield, they have these new (well, newish) window tints out that are mostly clear and can be installed on a windshield, but block a good percentage of the heat and infrared energy.

No comment on the legality of these tints, but I was considering the 90 or maybe 70 tint below on my GMC's windshield:

http://www.3m.com/3M/en_US/company-us/all-3m-products/~/3M-Automotive-Window-Film-Crystalline-Series?N=5002385+3292716668&rt=rud

From what I understand, they are clear enough not to attract any attention from John Q. Law, and not impede in any significant way, your night vision....


Mark S. '73 Painted Desert, Manny 1 Ton Front End, Howell Injection, Leigh Harrison 4bag and Rear Brakes, Fort Worth, TX
Re: [GMCnet] Engine driven roof top AC to replace Dash AC [message #321507 is a reply to message #321486] Tue, 01 August 2017 18:21 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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Registered: March 2004
Location: Americus, GA
Karma: 9
Senior Member
Last weekend Hubert Rowell showed me the tint of that type he'd just put on
his GMC windshield. He did the upper 2/3, leaving the lower untouched. I
had trouble seeing the transition at first. He says it makes a BIG
difference in cockpit heat. He didn't mention the density spec., but I'd
guess it was 70.

Ken H.

On Tue, Aug 1, 2017 at 1:31 PM, Mark Sawyer wrote:

> 2 Comments:
>
> Keep in mind, the A6 output quotes are at compressor rpm, not necessarily
> engine rpm. Not sure if the compressor is underdriven or overdriven, but I
> believe it is overdriven.
>
> As for the heat through the windshield, they have these new (well, newish)
> window tints out that are mostly clear and can be installed on a
> windshield, but block a good percentage of the heat and infrared energy.
>
> No comment on the legality of these tints, but I was considering the 90 or
> maybe 70 tint below on my GMC's windshield:
>
> http://www.3m.com/3M/en_US/company-us/all-3m-products/~/
> 3M-Automotive-Window-Film-Crystalline-Series?N=5002385+3292716668&rt=rud
>
> From what I understand, they are clear enough not to attract any attention
> from John Q. Law, and not impede in any significant way, your night
> vision....
> --
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Engine driven roof top AC to replace Dash AC [message #321515 is a reply to message #321486] Tue, 01 August 2017 22:03 Go to previous messageGo to next message
Jp Benson is currently offline  Jp Benson   United States
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Location: Fla
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Senior Member
TR 1 wrote on Tue, 01 August 2017 12:31
2 Comments:

As for the heat through the windshield, they have these new (well, newish) window tints out that are mostly clear and can be installed on a windshield, but block a good percentage of the heat and infrared energy.

http://www.3m.com/3M/en_US/company-us/all-3m-products/~/3M-Automotive-Window-Film-Crystalline-Series?N=5002385+3292716668&rt=rud



Looks like good stuff considering the substantial heat load that comes through the windows. I'm curious - has anyone estimated the heat load from having the HVAC box on the outside of the firewall?

JP
Re: [GMCnet] Engine driven roof top AC to replace Dash AC [message #321751 is a reply to message #321461] Mon, 07 August 2017 08:46 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Location: Belmont, CA
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Senior Member
If you know how to set the Vintage unit it does not block the hatch. Those that have no imagination can mount it half ass and complain and mislead.
Who would know more than us as we not only are an authorized dealer but been doing them for years on GMC coaches.
Quit passing out bad info.
I'm not Trump, but I can bitch, as I can't Tweet

Sent from my iPhone

> On Jul 31, 2017, at 6:02 PM, Thomas Pryor wrote:
>
> As Johnny Bridges stated the output of our A6 Compressor is an impressive
> 26000 BTU at 2000 RPM. We are just not able to distribute it efficiently
> and effectively, just say'n. I have a new vintage air unit that I can
> place under living area furniture if required. Don't plan to plumb it in.
>
> Some have said that the modification will block the engine hatch
> access...........no it won't. See: http://www.gmcmhphotos
> .com/photos/i-need-more-air/p63452-f-img-09691.html
>
> Also some comments that the return air duct is not shown in my images.
> Again looking at the same image the firewall recirculating opening is shown
> but not blocked off yet. That will be completed when I reinstall the IP.
> http://www.gmcmhphotos.com/photos/i-need-more-air/p63452-f-img-09691.html
>
> ALSO, IMHO ducting air thru the recirculating vent will only create more
> turbulent air flow and not solve the air management problem.......The air
> flow must come from lower quadrant and behind the HVAC
> Box.......................KISS! knuff said.
>
>
> Regards,
>
> Tom Pryor
> 4188 Limerick Dr
> Lake Wales, Fl 33859
> Cell 248 470 9186
>
> Living on a waterfront is not a matter of life or death. Its more
> important than that.
> _______________________________________________
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Engine driven roof top AC to replace Dash AC [message #321763 is a reply to message #321751] Mon, 07 August 2017 09:49 Go to previous message
powerjon is currently offline  powerjon   United States
Messages: 2446
Registered: January 2004
Karma: 5
Senior Member
Jim K
I have one the Vintage Air units to install in our Avion to enhance the AC. I got it from Bill Michell about 2 years ago. Why don’t you put the installation instruction up in your “Instruction” area. If not, what do you have that you can send be before I start the installation.

I will see you at the GMCMI Convention.

JR Wright


> On Aug 7, 2017, at 9:46 AM, Jim Kanomata wrote:
>
>> http://www.gmcmhphotos
>> .com/photos/i-need-more-air/p63452-f-img-09691.html


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J.R. Wright
GMC GreatLaker
GMC Eastern States
GMCMI
78 30' Buskirk Stretch
75 Avion Under Reconstruction
Michigan
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