Originally Posted by bansil
5050btu will make the back 12 feet(sealed off) a meat locker with factory roof, black windows and the sidewalls I did.
this is 90* with 90% humidity plus last weekend 65* is what back room probably averaged(with infrared hand gun....why do people just have to see what temp female boobs are?)
the front unit still needs some work....hopefully this weekend
then I have another (or 2 window units) should be cold with lower amp pull than root units...we shall see
the humidity is kicking our azzzzz's
Showoff! Rub your "cool" temps in why don't you!
Thank God it's going to cool down to the 90's next week.
Good rule of thumb... AC units will drop your temps by 10F to 20Fdegrees. Sometimes as much as 23 degrees. But no matter how well you have insulated you bus, it's still poorly insulated. I figure you need to reduce the square footage the AC is supposed to cool by 25%-30%. Possibly more.
Altitude (I mean HIGH altitudes over 5K) lowers the ability for your AC to cool. But then it's usually pretty cool at those temps.
In a central NM valley...
Late afternoon gets pretty warm in our bus. Sun is shining in pretty good at that time. Otherwise with temps as high as 108F the interior is cooled down 23F degrees cooler. So that means it's holding at 85F with a temp swing of 5 degrees +/- between kick on/off (we do not have it blowing constantly). Today's high was 109F. Our bus is 40 ft. GE 5050 BTU in the rear, GE 6400 BTU in the front. When the rear unit dies (older unit) we will replace with another 6400 BTU (it has a remote control and a digital thermostat
). In the mornings before it gets so sickeningly hot and in the evening when the sun has dropped below the trees (around 6:30), the units get it pretty cool. We've got another two months of this!
What helps: Avoid the direct sun. Shade is your friend. Glass magnifies the sun's rays so close your THERMAL curtains. Have a light coloured roof (we have Henry's SolarFlex roof coating on our roof to reflect the suns rays and to provide a thermal break between the exposed rivets on the exterior and the exterior heat/cold). Insulation with a radiant barrier. Break the thermal link. Every rivet/screw exposed to the exterior will pull the heat from outside into the next thermal conductor (like a metal frame), and it keeps going. Move to a part of the country where cooler temps prevail.
I would suggest that, like a generator, you buy as big a unit as you can afford and fit in the space you have. Based on measurement, I think the 8K BTU unit would have fit. But in our case we are trying to stay on a 30 amp hookup so we decided the 6400 BTU unit would supplement the 5050 BTU unit nicely. Our bus is split almost into equal halves. The part closest to the center (the bathroom where I do NOT want it freezing cold) stays fairly warm all the time as the rear AC unit really doesn't have the power to cool that much poorly insulated space. The front AC unit does cool all the way to the divider between the shower/bath area and the galley. All we have up right now is a fabric shower curtain to divide the front half from the back half. Amazing what that thin bit of material does. Eventually it will be replaced with an accordion door.