Keeping cool

I love a cold RV when sleeping.

If you have a proper thermostat for the air conditioner, just set it to the temperature you want; it won't cool down faster with a lower thermostat temperature setting.

What I generally do when driving is use the vehicle air conditioner and have a rear ceiling vent open (one with a vent cover over it) to help pull the cool air through the vehicle. The truck air conditioner is theoretically a good bit more powerful than a roof air conditioner, though it's somewhat limited by what sort of airflow you can get through the coils (and not helped by having the ductwork directly above a big hot engine). I think it's somewhere in the vicinity of 25,000 to 30,000 BTUs.

Upon arriving at a camp site, if the interior of the RV is hotter than the outside air, opening the vents and windows will cool it down rather more quickly than an air conditioner can. I'm not sure running the air conditioner during that time has much bearing on things; the basic goal is just plain old air exchange. Maybe runnign the air conditioner's fan would help in some cases.

If you’re asking about cooling as you go down the highway, open only the rearmost roof vent and set the dash A/C to point as many vents as possible straight down the back with the fan on highest setting.

Do NOT set it to ‘max A/C’ which will close the air intakes and defeat the point of the rear roof vent being open, which is to vacuum hot air out and replace it will cooled / dehumidified air.

A Ford E-series dash A/C system is nearly as much cooling capacity as 2 rooftop units.

Thanks. Are there any concerns about the wind ripping off the vent cover if it's open on the roae?

Four Winds Guy wrote:
Thanks. Are there any concerns about the wind ripping off the vent cover if it's open on the roae?

Not if you have a vent cover over your vent lid. They are designed to let your vent lids open all the time.
I would suggest getting the Maxxair covers,they will make your vent lids last longer.

The covers are constructed of high density polyethylene with maximum UV inhibitors for years of worry-free protection,unlike the others on the market today plus a 6 year warranty.

Four Winds Guy wrote:
Thanks. Are there any concerns about the wind ripping off the vent cover if it's open on the roae?

Absolutely...... Ask me how I know.......

If you want to drive down the highway with them open I would recommend something like this :

https://www.rvupgradestore.com/Maxxair-Translucent-White-Roof-Vent-Cover-p/31-1919.htm?gclid=Cj0KCQjwpavpBRDQARIsAPfTwizTXUtIsidLU7PYefDI-4FCxjfI7Eh7_RNOTeyx_m6NC5a0RqdKUp0aAnXQEALw_wcB&gdffi=d722fab84a06472899ce2a16e4d2ed3f&gdfms=A6A1B0E895C54C0F928778E7F79DC11D

In really hot weather I run my generator and roof air. It's a fifth wheel so hopefully dash air.

Sorry, my link does not work. It is a maxair roof vent cover.

Four Winds Guy wrote:
How do other Class C owners stay cool in the hot summer months?

Do you drive with generator on and air conditioner running? Or do you use the engine air conditioning on the road with generator off, and open the vents to release hot air when you stop?

And does starting the A/C plugged in at a campsite with the roof vents open speed up the cooldown?

We're returning to RVing after 10 years and trying to re-learn all the tricks. Once we plug in at a campsite and turn on the A/C high, it takes a while to get cool, but if we forget to turn it down, we'll be popsicles in the morning.

We just use the dash air set to a reasonable temp like 20C (sorry Euro-thermostat), start if off on "recirculate", and close all the roof vents and windows. It seems pointless and self defeating to cool the interior air and then suck it out through open vents. When we leave the coach parked to run errands, we might fire up the generator and start the roof air to keep things cool while we're shopping or whatever. Of course, we try to be as far away from humanity as possible, if we choose this option, to reduce the "audible" annoyance.
We were just out this afternoon/evening, and this methodology worked very well.

We keep all rooftop vents and windows closely tight during hot weather travel in our 24 foot E450 Class C. We then keep the dash air flow and dash air conditioning system set to Max A/C so interior air is merely reciculated over and over - hence the Ford air conditioning system does not have to continuously cool new hot air from the outside - it just has to keep the already cooled interior air cool ... which is a way more efficient way to use the dash air's cooling capacity.

What we wind up with is an entire coach interior that can be kept cool using only the Ford A/C system ... because it's so powerful and we're using it in the most efficient way. Our rooftop A/C system never is needed when traveling in even the very hottest outside temperatures.

As a bonus, the interior of the coach stays dust-free much longer because there is no constant flow of outside air coming into it from the cab air flow set to constantly get new outside air ... which then flows throughout the coach and out any open vents or windows in the coach ... depositing dust inside while this is going on as we travel down the road.

If we ever need to leave the roof vents open for some reason when traveling, they're protected from being ripped off via vent covers we've installed over them which still allow the vents to remain open. With vent covers, we can also leave the vents themselves open for fresh air ventilation when it's raining or snowing while camped.

My solution is to head to the mountains.