S-280 air conditioning

[m16ty]

Anybody have any idea on how big of A/C unit it would take to keep a S-280 cold in the summer? I've searched the web and several RV sites but I'm getting conflicting information.

I've been looking at the small split units as my S-280 doesn't have the big holes in the front to mount A/C. I figure I can just drill a couple of small holes easier than I can install a window unit or roof mount. I also worry about a roof unit getting torn off from a low limb.

 

[NDT]

My S280 Battery Shop has twin 9000 BTU Mil window units, so a 18,000 BTU (1.5 ton) mini split should do it.

 

[m16ty]

I figured one 9k would do it but you may be right. Mini splits that big (18k) are kind of pricey.

 

[NDT]

Go with the 9000 then. The rule of thumb is one ton for every 400 sq ft. You are way under 400 sf.

 

[richingalveston]

It does depend somewhat on what you plan to put in it. You have to consider the internal heat load, external temp and the solar gain (how much the sun warms it up) which is the biggest problem.

For solar gain you could also try painting it with the ceramic additive. supposed to make a huge difference on solar gain.
A solid roof rack with about an inch air gap between it and the roof would make a huge difference.

A 5K btu unit would work if it were just a couple of people inside and no solar gain to deal with, the solar gain alone could double this.

Split systems are expensive and probably do not get much smaller than 12000 btu.

You can split a window unit that you buy off the shelf if you have some HVAC experience.
You just have to add another fan and motor and build a rack for the exterior coil and a condensation pan and drain.

Also building a shade cover for the exterior unit is a big help in efficiency.

Rich

 

[quickfarms]

I currently have a 5000 BTU window unit in mine and it is small for the S280. This is just for me camping in it.

My roof is painted with white elastomeric roof coating. Sides are painted USMC green.

Thing to consider are exterior color, roof color, weather the S280 is in the shade, internal heat load and exterior temperature.

I do like the idea of two 9000 btu units, especially if they have heat. One would probably be sufficient in most situations but the second one would be welcome if it gets two hot of the first one fails.

 

[brianrbull]

Mine Came with 2 18,000 BTU units and I can draw her down to high 50's in there before the thermostats pop.....

 

[m16ty]

Basically I just want it cool to sleep in. In the past we've just been sleeping under the cargo cover and it's hard to sleep on those hot summer nights. It would be nice not to walk into a oven going in there during the day but that's not a main concern.

My power source will be generator power so I'll rarely run the ac during the day to conserve fuel.

Internal heat load will just be what up to 4 bodies will put off. I'll probably also paint the roof white to help.

In my short search I have seen small split units with 9k btu.

 

[quickfarms]

If you are not running the AC during the day you will want ventilation to get rid if the excess heat

 

[richingalveston]

9000 would be plenty. If you are going to paint, consider this:
http://www.ceramicadditive.com/insulating-paint-additive.html

Not expensive, I plan to do my rv someday. It worked well for a friend.

 

[m16ty]

The more I research this, the more confused I am.

If you use any of the online BTU calculators, you come up with around 3,000 BTU taking the square footage of the shelter. But when you surf the RV sites people with real world experiences say that I'll need at least 9,000 BTU.

I haven't even picked the shelter up from the GL lot yet but I'm going to have to jump on the camper conversion as soon as I get it though so I'll be ready for the camping season.

 

[RAYZER]

The more I research this, the more confused I am.

If you use any of the online BTU calculators, you come up with around 3,000 BTU taking the square footage of the shelter. But when you surf the RV sites people with real world experiences say that I'll need at least 9,000 BTU.

I haven't even picked the shelter up from the GL lot yet but I'm going to have to jump on the camper conversion as soon as I get it though so I'll be ready for the camping season.

You may be able to get away with a 5000 btu window shaker.