A/C Lovers look here

As some have hinted above, it also matters how an A/C is ducted and used.

Our small 24 foot Itasca (Winnebago) Class C has a single 13.5K BTU A/C, but it is fully ducted in the ceiling along the entire length of the motorhome, including in the ceiling area above the cabover bed. Each duct can be individually opened or closed, including any amount in between. This really makes it possible to configure the A/C's output to any conditions and, IMHO, is the best way to make an RV's A/C maximally effective.

We haven't tried Florida yet, but so far on RV trips in the Texas Panhandle and the Southern U.S. during July and August ... our single A/C unit with it's ducting system has been adequate whether hookup camping or dry camping using the built-in generator.

One nice feature of a Class C motorhome built on a Ford chassis with the V10 engine is ... for a fast cool-down in scorching weather one can both run the rooftop A/C using hookups or a generator - while at the same time idling the V10 engine with the cab A/C set on high settings for awhile. We have used both of these air conditioners at times for super cooling under scorching heat conditions. Ford E-Series chassis have cab A/C systems with tremendous capacity - well beyond single rooftop RV units.

Just added 2nd AC to our 31' Class C. 100-110f in CA,AZ, & NV was too hot for just one.

For sleeping, it' rare to need 2 air/con units. Without the sun beating down, it's much easier to cool an RV.

As others have mentioned, size matters more than class. A new 35' Class C will typically come with 2 air/con units. A small 25' Class A will likely have 1 air/con unit. What you are seeing is Class A units typically are larger than Class C (but of course there are exceptions)

suprz wrote:
Not sure, but do some Super C's have 2 A/C's? But you are talking over 35 ft in length

My 35' Super C had 2 A/C's. It also had 50 amp shore power. Very seldom used both at same time.

Not sure, but do some Super C's have 2 A/C's? But you are talking over 35 ft in length

larry cad wrote:
FWIW, we have a 40' class A. We have two A/C units. Both are ceiling ducted, with the duct running from front to back. Typically, we run the rear A/C unit during the day to primarily cool the front where we spend our time. At night, we run the front A/C to cool the bedroom. There are several vents along the length of the duct and we close them or open them as need arises. The huge advantage is that we cool the area where we are but it is very quiet where we are. In a C, the single A/C unit is typically pumping out the cool right above your head, in a noisy way. Try it and you will see what I mean.

Ditto. We do the same. Only time we run both when 90 and above.

FWIW, we have a 40' class A. We have two A/C units. Both are ceiling ducted, with the duct running from front to back. Typically, we run the rear A/C unit during the day to primarily cool the front where we spend our time. At night, we run the front A/C to cool the bedroom. There are several vents along the length of the duct and we close them or open them as need arises. The huge advantage is that we cool the area where we are but it is very quiet where we are. In a C, the single A/C unit is typically pumping out the cool right above your head, in a noisy way. Try it and you will see what I mean.

Depending on length. A single AC is fine for under around 27 feet. Of course, parking in full sun in FL in the summer nothing will keep you cool.