asking for advice,from afganistan

[rmtech]

HI everyone I haven't been on here in a while due to being sent overseas, I've got a problem i'm hoping one of you can help me with,I need to find out what size BTU window shaker I would need for rooms that are 10 by 10 and would hold one or two soldiers. these are sleeping accomodation.I am dealing with up to 50 degree celsius temperatures here and I want to make life a little better for the guys, some rooms have old window A/C in them but they are 17,500 btu I think these are way oversized as they make the rooms feel damp and they run and shut off over and over. Any help you could offer would be great.

[iraqveteran]

get a couple different sizes and try em out.

[beenthere]

As above, either do a load calc. Or, try a 12,000, a 8,000, etc. Until you get the right size.

[digital686]

Try the Mitsubishi 9500 or 1200 btu mini split. This should do the trick. I know when I was in Desert Storm we had 8 window shakers cooling a portable office unit because it was so friggin hot. We'd come to work at midnight, the outside temp would be about 105 and we'd just turn them all on and go to the mess hall for an hour.

http://www.minisplitacunit.com/mitsu...ditioners.html

[sparksandfan]

Any insulation in the walls or ceiling?

Are the walls and ceiling raw plywood?

What color is the roof?

Any windows? Single pane?

Raised floor, no insulation? Concrete slab?

[rmtech]

the walls are plywall with styrofoam insulation and a white tin outer skin. the roof is white tin as well,and the windows are double pane, the building is raised up on pillers about two feet of of the sand base. I would also like to thank you all for your advice, but I can't buy several types and try them as this is not an offical project, we are trying to get it right the first time without raising to many concernes with the money counters,the last thing I need is to have this project stopped before I can get the job done.for some reason the powers that be don't seem to think A/C is needed for the NCM shacks. thanks for your help

[beenthere]

Whats teh R value of the insulation, roof and walls.

[sparksandfan]

Rmtech, since these are for sleeping only, what we are trying to get to is the heat coming in, and air infiltration.

I take it that we can't assume that duty stations are only during the day. It makes a big difference if we are only talking night on the heat loads.

What is the linear outside dimension of the windows, that is, the total length of air infiltration? Weatherstripping or not? How is the door weatherstripped, if any? Is the door homemade?

How tight are the plywood walls? Can you feel air moving between the studs and plywood? Between the sole plates and plywood? Plywood and ceiling joists?

Any insulation under the subfloor?

[rmtech]

The windows are 3 feet by 3 feet one per bedroom,and the buildings house twenty rooms with two personel to a room on average, these rooms are living areas that are used day and night they have north and south windows depending on the layout,the room doors open into an un a/c hall way the buildings are built well without alot of air movement infact this whole area seems to have no air movement anyway the out door temp is about 40 degrees C 104 degrees F and it is expected to reach 60 by the end of the month,and the night time temperature sits at about 28 to 35 c / 82.4 to 95 F, anyway thats about all i can give in the way of info as to the build stucture other that the fact that its damn hot in there. thank for your help.

[firecontrol]

I know this is going to sound......... well dumb. But if you have access to some electric heaters, try running them at the same time in the room. Add the extra btu's to make the ac's run longer.

[beenthere]

I won't say that sounds dumb.

But wouldn't that be difficult to explain to the money counters.

Hey Mr. money counter, I want to buy electric heaters to use in the desert when its only 110* outside so we can run the ovder sized A/C.

[sparksandfan]

OK, these are not precise numbers as the inputs are unknown, your mileage may vary, etc.

When the real heat arrives at 140*F, then the 17,500 Btu/hr units are not that far off. Including some drop in efficiency for 140*F, 15,600 Btu/hr would be close to what is needed.

However, in 95*F, only about 6,000 Btu/hr is needed. And that's why it is damp now in the room.

One possibility would be to gang the units so that you go up progressively 6,000 Btu/hr with the seasons. A max of 3 units per room. Or find a multistage system. Or big units to cool the whole barracks.

But only you know your electrical, logistics, transportation, etc. limitations.

[rmtech]

thank's to everyone for the advice,its hard to give numbers with the security issues,so I do thank you for doing the best you can with what i was able to give,as for the heater Idea, i'll have the room windows opened a crack that should up the heat load and allow the units to run longer. thanks