Seems like the bigger 5th wheels and trailers all have dual ACs and I assume 50 amp. Not all campgrounds always have 50 amp spots available and not all generators can handle dual ACs.Am I right in thinking that finding an RV with single AC is more versatile or do the dual somehow manage with only one running?I was in Moab and Las Vegas lately with temp around 100 and the single 13.5 in my 20' was working all the time just to keep temperature survivable.

Fastfwd75 wrote:Seems like the bigger 5th wheels and trailers all have dual ACs and I assume 50 amp. Not all campgrounds always have 50 amp spots available and not all generators can handle dual ACs.Am I right in thinking that finding an RV with single AC is more versatile or do the dual somehow manage with only one running?I was in Moab and Las Vegas lately with temp around 100 and the single 13.5 in my 20' was working all the time just to keep temperature survivable.our 30-amp model year 2000 Irasca has dual AC's and an energy management system that allows both to operate. as we approach maximum draw the system begins shifting other systems to LP...water heater, fridge...or shutting them down altogether...high speed fan and finally the second AC.

Some folks will install the second A/C unit on a separate 120VAC 20AMP circuit that they can plug into the camp ground 20AMP Service which most have...We use the 20AMP Service pedestal all the time with our trips. In the winter months this runs our extra oil-filled heaters...The 20AMp Service from the pedestal does not take away from your 30AMP service. It has its own circuit breaker on the campground pedestal.If you can't find a 20AMp service receptacle to plug-in to then go ahead and plug into one of your 15AMP receptacles and turn off alot of other things if you have too allowing you to run both air conditioners.There is also another solution which is starting to become popular and that is one of those portable air conditioners. They just plug into your 15 AMP receptacle and need to have a close by window for the exhaust to go thru. These A/C units can be a 5K or bigger but are great for one room like the bed room... A couple of choices here...Roy Ken

I can run both on 30 amp,just start 1 at a time or use any other high amp appliances microwave,toaster at the same time ken

Fastfwd75 wrote:Seems like the bigger 5th wheels and trailers all have dual ACs and I assume 50 amp. Not all campgrounds always have 50 amp spots available and not all generators can handle dual ACs.Am I right in thinking that finding an RV with single AC is more versatile or do the dual somehow manage with only one running?I was in Moab and Las Vegas lately with temp around 100 and the single 13.5 in my 20' was working all the time just to keep temperature survivable.Dual ACs are probably rarely necessary in a 20' RV. However, when an RV is over 30' long, there is a lot more space to cool and a lot of cooling capability is lost in the poorly insulated duct work. Dual ACs also allow you to cool a sleeping area without cooling an entire large RV.

Dual AC a handicap when only 30amp is available?

17 Replies

tpi
Explorer
Jul 31, 2014
I personally think if the RV is big enough for dual AC units, it should have dual AC units. At worst you can always run one of the two. If you're looking for single AC, I'd buy a rig within the capability of just one AC.

This is coming from someone who travels in desert southwest.
paulcardoza
Explorer
Jul 31, 2014
I thought it was just me! ;-)

RockyMt wrote:
If hooked to 30amp I just run one air conditioner,I don't see what the problem would be.
wa8yxm
Explorer III
Jul 31, 2014
Well.. Since it appears I am not going anywhere for a while I put my 50 amp rig on a 50 amp long term site. But back when it was more mobile I ran into that 30 amp site issue many times.

Original wiring for coach

Breaker box--20 amp---------Rear a/C

current config

Breaker box--20 amp------Outlet/Plug---20 amp----Rear AC

(20 amps refers to a 20 amp breaker)

The plug and outlet are in an outside compartment,,,

Years ago there was a company (Power Solutions RV PSRV dot NET) the web site no longer is found... This was basically their design.

50 amp site: Plug into socket
30 amp site: Pull plug, use 12 ga Extension cord to connect to 20 amp park outlet.

NOTE I have seen Cheater boxes and cords that let you plug into both the 30 and 20 amp outlets then plug the RV into that.. THEY DO NOT WORK in many parks, (Any park with GFCI breakers) as they trip the GFCI's

This system I use, Does work.
Lantley
Nomad
Jul 30, 2014
In the end its not just about A/C a 50 amp rig/site has advantages over a 30 amp rig/site.
A 30 amp rig is fine and is very capable however a 50 amp rig requires no energy management or additional conservation.
Dual A/C's, multiple space heaters, hair dryers microwaves can be used without tripping the breakers.
K3WE
Explorer
Jul 30, 2014
RockyMt wrote:
If hooked to 30amp I just run one air conditioner,I don't see what the problem would be.

Back to the title of the thread- I see two AC's as an ADVANTAGE, offering flexibility...
wintersun
Explorer II
Jul 30, 2014
The longer the AC runs the more efficient it is in conditioning the air. Two smaller AC units will be more efficient than a single large one that will power on and then shut off and have a shorter duty cycle.
You also have a backup should one unit fail for any reason which in hot climates could be a life saver.

Historically the people building RVs and houses have been ignorant of AC systems and have put in twice as large a unit as is actually needed thinking that overkill was the prudent approach. Actually with the oversized AC units people were less comfortable thanks to the short duty cycle. More power is consumed with less conditioning of the air actually taking place.
RockyMt
Explorer II
Jul 30, 2014
If hooked to 30amp I just run one air conditioner,I don't see what the problem would be.
mowermech
Explorer
Jul 30, 2014
Our coach has two A/C units, and both will run with 30 amp service, no problem.
the coach is wired for 30 amp service.
On a 90 degree day, with both units operating, it actually gets COLD in there!
Atlee
Explorer II
Jul 30, 2014
A friend of mine recently bought a used 34ft Airstream. It has 30 amp service but has a second AC. The second AC has it's own dedicated 20 amp cord to plug into a pedestal.

RoyB wrote:
Some folks will install the second A/C unit on a separate 120VAC 20AMP circuit that they can plug into the camp ground 20AMP Service which most have...

We use the 20AMP Service pedestal all the time with our trips. In the winter months this runs our extra oil-filled heaters...

The 20AMp Service from the pedestal does not take away from your 30AMP service. It has its own circuit breaker on the campground pedestal.

If you can't find a 20AMp service receptacle to plug-in to then go ahead and plug into one of your 15AMP receptacles and turn off alot of other things if you have too allowing you to run both air conditioners.

There is also another solution which is starting to become popular and that is one of those portable air conditioners. They just plug into your 15 AMP receptacle and need to have a close by window for the exhaust to go thru. These A/C units can be a 5K or bigger but are great for one room like the bed room...

A couple of choices here...
Roy Ken
Aridon
Explorer
Jul 29, 2014
You can run 2 15k AC's on 30 amps pretty easily. Just start them at different times. We did it for a summer while taking care of family a few years back.