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Re: [GMCnet] Dual CS single A/C [message #351627] Wed, 15 January 2020 05:15 Go to next message
johnd01 is currently offline  johnd01   United States
Messages: 354
Registered: July 2017
Location: Sacrameot
Karma: -1
Senior Member
30 amp shore power is not a problem. It comes into the coach as 220 volts
with one hot leg on each side of your circuit breaker box. you will only be
pulling less than 15 amps on each leg that can do 30 amps each. I like
keeping your original unit as backup/extra cooling. That way you get 27k if
you really need it.
My coach is wired with the back AC unit as the only load on one leg. The
rest of the coach is on the other leg.

On Tue, Jan 14, 2020 at 8:36 PM Flavio Andrade via Gmclist <
gmclist@list.gmcnet.org> wrote:

> My 78 Royale has a single original Duo-Term 13.5k BTU roof A/C that is
> working well. However, I live in Florida and plan on camping during the
> summer (think 95+ degree days). I don’t think the 13.5k will handle one of
> these very hot days (I like it nice and chilly inside). Here are two
> options I’m considering:
>
> - replace the original 13.5k with a 15k Coleman Mach 10 (I love having the
> digital control and Bluetooth);
>
> Or
>
> - keep the original 13.5k and add a second unit. In this case I’d go with
> the 13.5k Mach 10 NDQ (quiet version). I’d run the latter primarily and in
> a very hot day I’d use the old Duo-Therm as a second unit. Another benefit
> is the redundancy (if one breaks down during a trip, I still have the other
> :)
>
> I really like the quietness of the NDQ, but at 13.5k it may require a
> second unit on a hot day.
>
> My questions: do you guys think a single 15k unit can handle 95+ degree
> days? Also, will the 30 AMP shore line be able to handle two 13.5k units
> running simultaneously?
>
> Thanks!
>
> ///Flavio
> andradef@me.com
> 78 Royale RB
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>


--

*John Phillips*
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Johnd01 John Phillips Avion A2600 TZE064V101164 Rancho Cordova, CA (Sacramento)
Re: [GMCnet] Dual CS single A/C [message #351629 is a reply to message #351627] Wed, 15 January 2020 06:19 Go to previous message
Ken Henderson is currently offline  Ken Henderson   United States
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
Senior Member
Sorry, John, but that's not the way the GMC's 30A circuit works: It
supplies 30A at 120vac ONLY -- NO 2 legs.

Modern low-current A/C's MAY be able to run on a single 30A circuit if
there's little other loading. But, what most of us have found necessary is
the installation of a separate dedicated supply cable for the second A/C.

Even with that requirement, my recommendation to Flavio is to install a
second A/C. My 23' has a modern 13.5 A/C, is well insulated (including
"honeycomb" blinds), and has a cockpit curtain which can isolate that area
pretty well. Even with all that, here in GA and other southern areas we
still sometimes can't keep the interior temperature below 80*F. His 26'
will probably have at least 10% higher cooling needs.

Ken H.

On Wed, Jan 15, 2020 at 6:16 AM John Phillips via Gmclist <
gmclist@list.gmcnet.org> wrote:

> 30 amp shore power is not a problem. It comes into the coach as 220 volts
> with one hot leg on each side of your circuit breaker box. you will only be
> pulling less than 15 amps on each leg that can do 30 amps each. I like
> keeping your original unit as backup/extra cooling. That way you get 27k if
> you really need it.
> My coach is wired with the back AC unit as the only load on one leg. The
> rest of the coach is on the other leg.
>
> On Tue, Jan 14, 2020 at 8:36 PM Flavio Andrade via Gmclist gmclist@list.gmcnet.org> wrote:
>
>> My 78 Royale has a single original Duo-Term 13.5k BTU roof A/C that is
>> working well. However, I live in Florida and plan on camping during the
>> summer (think 95+ degree days). I don’t think the 13.5k will handle one
> of
>> these very hot days (I like it nice and chilly inside). Here are two
>> options I’m considering:
>>
>> - replace the original 13.5k with a 15k Coleman Mach 10 (I love having
> the
>> digital control and Bluetooth);
>>
>> Or
>>
>> - keep the original 13.5k and add a second unit. In this case I’d go with
>> the 13.5k Mach 10 NDQ (quiet version). I’d run the latter primarily and
> in
>> a very hot day I’d use the old Duo-Therm as a second unit. Another
> benefit
>> is the redundancy (if one breaks down during a trip, I still have the
> other
>> :)
>>
>> I really like the quietness of the NDQ, but at 13.5k it may require a
>> second unit on a hot day.
>>
>> My questions: do you guys think a single 15k unit can handle 95+ degree
>> days? Also, will the 30 AMP shore line be able to handle two 13.5k units
>> running simultaneously?
>>
>> Thanks!
>>
>> ///Flavio
>> andradef@me.com
>> 78 Royale RB
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>
>
> --
>
> *John Phillips*
> _______________________________________________
> 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


Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
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