too shiny for the desert?

nettepdx · 07-11-2005, 01:27 PM

so here i am in southern arizona, almost 30 days of 100+ degree days and i've been 8 days without AC. long story about burned-out parts and delay in getting replacements, blah blah blah. but to get to the crux of the matter: the guy working on this problem "hates" airstreams and he said because of the aluminum, in this hot sun, i will always be burning out AC parts. i can't believe that's true.......is it? i know of talk here on the forum of people painting their trailer roofs (rooves?

) white. he also said that periodically i should hose the thing down. anyway, i'm just curious because when i think desert and trailer i think "airstream". any thoughts? btw, i have a dometic penguin (which was installed july 2 2002 and the AC went out on.... [drumroll]...july 3, 1 day after the warranty expired).

**Janet** · 07-11-2005, 01:38 PM

Bummer! Come north - it's cooler and we miss you.

I don't know anything about AC but... one of the most common reasons I see in my work for equipment failures in low voltage from electrical outlets. Stuff runs hot and then blows up.

**Stefrobrts** · 07-11-2005, 01:42 PM

The whole point of being mobile is to head north when it gets too hot, and south when it gets too cold

Seriously, I hope you make it back up this way again sometime. How about the second annual Beverly Beach rally in October?

Good luck with the AC problems!

Ferroequine · 07-11-2005, 01:48 PM

I have a theory that now that I've polished the trailer, it should actually be a few degrees cooler inside than before, due to all of the heat bouncing back off it with the reflection -- sorta like the space wrap they put on sattelites.

Can anyone else confirm?

Ken J · 07-11-2005, 01:48 PM

This guy needs to get a life - an Airstream won't "burn out" a/c's anymore than any other trailer - I agree with the above - low voltage toasts a/c units. Do you have a line voltage tester plugged in all the time? If not you may want to get one.

Ken

nettepdx · 07-11-2005, 02:18 PM

the low voltage thing makes sense as the whole infrastructure at this park is a bit, shall we say, weak. i don't have a voltage tester but when the guy comes out on tomorrow (fingers crossed) i'll have him check that.

i miss you girls (and guys) in the north, too. i know this trailer living is supposed to be "mobile" but.....well, hell, i've been sucked into a southern arizona vortex and I can't get out. it's hard to explain. but i tell you, i sure picked a great summer to see if i could endure the airzona heat!

i am keeping the 2nd annual beverly beach gathering in my sights (and i'd like my same pull-through site please

)

Ken J · 07-11-2005, 02:56 PM

I highly recommend that you get a voltage meter - Camping World has them for about 20 - because when you a/c guy gets there all may be well - then in the evening when everybody cranks up the a/c the voltage will drop -

Ken

bobechs · 07-11-2005, 03:08 PM

Bad power is certainly hard on A/C units. I do belive that is the proximate cause of any burn-outs.

That said, bare aluminum, polished or otherwise, is not an efficient surface to minimize radiant heat load accumulation in the overall trailer system. That accumulated heat has to go somewhere and along the way that means thru the refrigeration cycle in the A/C which is hard, expensive work. Bad power makes the problem dangerous to the A/C as well. While polished or bare aluminum has decently high reflectance, at least compared to black or dark colors, the emittance (which measures the ease with which the surface gives back energy to the outside) is pretty low.

The ideal suface for solar heating is one with low reflectace and high emittance. Once again, think of a perfect black at all solar wavelength. But we don't want a perfect solar heater. What we want is the worst solar heater we can design. The best we can hope for is a complete thermal break. The best practical manifesttion of that is deep shade; no energy incoming means none to dispose of.

Failing the availability of shade, the next best thing is a surface with high reflectance and high emitance. White paint is about the best you will find in this regard.

Remember when the astronauts went into space? The first suits, not intended to leave the capsule were a shiny silvery material. Tres chic. In the "shade" inside the capsule there was no reason to worry about radiant heat accumulation. But in open space and on the moon, white was the color of choice to minimize solar heat load. Even so, radiant heat management was still an important engineering problem.

So, to deal with heat build-up in the trailer you are best off to avoid it by seeking shade, not higher latitudes. If you can't do either of those, a white coating is far better than polishing.

bobechs · 07-11-2005, 03:39 PM

By the way, watch how hard your A/C works in the evening, after the sun goes down, compared to the mid-morning when the sun is high. Usually the outside air temperature is lower in the morning than the early evening, yet I bet the A/C runs continuously at mid-morning and intermittently after the sun drops even on very hot days.

Not that air temperatures are completely insignificant, but radiant heat is bigger problem for an exposed trailer in the Southwest, or anywhere with strong sun. The hot air does conductively heat the trailer and the infiltration of hotter-than-room-temperature air affects comfort. Also, it is a bit harder to reject heat thru the A/C coils into hotter air. But none of this really compares to the heat coming in from exposure to the blazing sun.

SafeHarbor · 07-11-2005, 07:03 PM

Hey, write to support@dometic.com. I have customers over there, and they are very proud of what they do and what they produce. I bet if you explain your one-day-over-warrantee problem, they'll take care of you.

Lamar

nettepdx · 07-11-2005, 09:04 PM

so in reading the posts from bobechs and ken j, it looks like i'm screwed. first off, with minimal shade to be found in the desert, and no desire to paint the top of my trailer, i'm stuck with the reflectant/emittant (?) problem. and if it is bad power, then it's a park issue and my only option is to move to another park, of which there is only 1 down here, which i'm sure has better power but it has a lot less shade.

anyway, i'll add a voltage meter to my list of things to buy but what good will it do other than to tell me when the power is low?

i'm confused.....must be heat stroke

surely there are other airstream desert rats out there who can offer some words of encouragement...

**flyfshr** · 07-11-2005, 09:19 PM

Hi Annette -
The summer's here are a tad warm but just think - its already July and there's only August and half of September left before we'll see 90 degrees again.

I have a ten year old Penguin Low Profile on mine and haven't had any problems but I don't run it all day and night. Where is it that only has two campgrounds?

FF

markdoane · 07-11-2005, 09:24 PM

Here's an idea. http://www.patiostore.com/coolshade/clear_portable.html

It's white. It folds up and fits in a large duffle.

nettepdx · 07-11-2005, 09:40 PM

oh great, thanks, FF! only 2 more months of this heat!!!! actually, what you said about your penguin is encouraging. i use my AC less than anyone else at this here park but once it's back up and running, i'll be sure to turn it off at night. i've been sleeping ok what with misting the bed, aiming the fan at it, and taking a tylenol pm

.

btw, i'm halfway between tucson and nogales, in amado.

and you Don, are you suggesting i put a canopy over the whole trailer? hey, i know, maybe i could just put a little tent over the AC unit!!!

i'm feeling better already. thanks.