cooling your tent or van

[unjonharley]

where is the air intake

[EmilyD]

There's a gap on the sides ands this will have a block of ice in it

[FIGJAM]

Sorry Emilie, but it won't be very efficient, and if it works at all it will go through ice like crazy.

[Monkeystyle]

I was just going to ay that... just seems like a waste of ice...

[sharpstick]

Another comment from a hvac forum:
"For efficient heat exchange between the wet pad and air, air flow needs to be turbulent.The optimum velocity will be around the 500-600 fpm mark.Too low a velocity will make the airflow laminar and there will not be efficient heat exchange."
Interesting idea, but I can't imagine what it would take to increase turbulence that wold be playa practical.

[FIGJAM]

Research shows that a cooler under ideal conditions will reduce the temp by 30 degrees.

I achieve that consistently on the playa!

The first 4 columns are the BRC sweet spot!!!

[sharpstick]

Forgive me for picking nits, but sometimes I put way too much time in details.
- The higher the water level, the less pad is exposed for airflow. This could be a variable if the air is not completely saturated by the time it passes through the pad.
- On Figjam's model, the holes are cut slightly above midline(probably to avoid the bucket ribs), If they could be cut higher up, there would be room for a higher fill level, (and possible decreased efficiency until the level drops.) One advantage of midline holes is that the air passes up and down as it enters, but I think this is minor.
- I found a 6 gallon bucket that is 17.5" high. I plan to drill the holes higher up allowing up to 5 or 6 gallon capacity if I drill 1 inch holes between the top frame ribs. (Brew store has them. They have 7 gallon 19" fermenters, too) The total area of the holes only has to be (at least)as large as the outlet fan, right? x 1.5 for good measure? (Wow. 4" dia = 12.57 sq in, 1" dia = .79 sq in, therefore, 1 x 4" hole = 16 x 1" hole = 4 x 2" holes!)
- Also considering a second reservoir bucket next to the main unit with a loop of siphon hose connecting them effectively doubling capacity. I could float the float switch in this one and keep it out of the way.
- Float switch - I haven't seen any mention of these. Has any one woken up sweating in the heat smelling a burned up pump yet? Or have you all been diligent and/or lucky in remembering to keep your water levels up? (Bear in mind the mental energy vortex existing within a five mile radius of the man base that sucks up all rational thought.)

I know, I know, I'm way overthinking the whole thing, but I'd rather overthink designing it sitting at home than overthinking fixing it sitting in the dust! and that's just the way my head works.

[sharpstick]

(just got back from page 51. forgive me if the answer is somewhere between there and page 87.)
How is the pad sealed at the top to prevent air from passing over the top of the pad instead of through it? Is it just cut long enough so that it is crammed up against the water ring and lid or what? If it is squeezed too much, wouldn't it buckle?

[FIGJAM]

Cut the pad tall enough so that the drip "halo" acts as a seal.

This will force all the incoming air through the wet pad.

[sharpstick]

sounds good.
Holes - The 4" diameter blower outlet is about 13 sq inches of area. How many holes of what size did you cut? I just cut 12 x 1 3/8" ones for 19 sq in of inlet area.

[FIGJAM]

I didn't calculate the area, I just drilled 2" holes with an inch between each hole.

Since the pad is about 1/4" from the bucket it allows for excellent air flow over the entire pad.

It works out to about 3x the intake compared to the size of the fan.

If you put this much thought into every aspect of your burn you'll never get there!

[sharpstick]

that works out to about 12 holes then. I can put in a second row if I have to, but I don't think I need it.
that's what I tell myself every year when I leave the pavement! How the hell did I get it all done? you should see my checklist!

[Sassi3]

Fig Jam, I can't thank you enough. my swamp cooler worked like a charm. I was in a truck and encased my matress in my tent shell and then strung a rope with a drape across the entrance. Since the temperature inside the truck was at least 5-10 degrees cooler then the outside air, It made for more efficient cooling to begin with. Then, as I pumped the air from the cooler into my sleeping chamber, it was perfect.

Two adjustments that I plan to make to my cooler.
1. I will get a strong computer fan.
2. AVOID the Aspen pads. They are moopy and hard to make adjustments too. I am ordering cooler pads now. The one you specifically recommeded does not seem to be available any longer, but I will experiment with a couple of other ones I found on Amazon that are reasonably priced.

Thanks again,
Sassi

[FIGJAM]

Don't give up on the dura cool pads!!!

If you have an ACE hardware store in your area, they will ship store to store for free. (it's company policy)

Find an ACE in PHX. with the pad you want and have your store get the pads from there. (should be $6 or $7)

It's getting hot here, so most of our hardware stores are stocking pads now!

[sharpstick]

I just got my pad from Sims. final assembly tomorrow. I'll test it in the house with AC on so humidity is lower.

[Roundabout]

Last week I got a Dura-Cool from eBay with no problem.

[EmilyD]

Sorry Emilie, but it won't be very efficient, and if it works at all it will go through ice like crazy.

How about if I wrap the block of ice in that blue stuff? This is only for an hour or two of cool. We just don't have space for anything larger (your bucket design) for our tiny trailer.

[FIGJAM]

If your trailer is under 600 cu. ft. the bucket cooler will work well and not need ice.

If it's a teardrop trailer, there is a design that can be built into a cupboard.

A picture would help.

[sharpstick]

50% humidity. I fired it up and got less than 2 degrees drop, but then I discovered that the pad didn't go all the way to the lid so air was passing above it. I pulled the whole thing apart and discovered that the pad had folded up at the bottom and had collapsed. It doesn't appear to be stiff enough to support itself. I'm going to make a hardware cloth cage to surround and support it. good thing i started this in april!

[LowePro]

"I'm going to make a hardware cloth cage to surround and support it."

Exactly what I did (well, chicken wire) and it worked great to keep the shape of the blue pad from slouching. Shape it so there is a ~1 inch gap between the inner wall of the bucket and the wire cylinder and you should be good to go.
The pad also seems to have a "grain" to it, so you could try different orientations of the pad to see if one direction is stiffer.

[sharpstick]

orientation is not a variable. It was only long enough in one direction, unless I buy a new larger piece and start over. I am gluing poly foam wedge spacers to the cage on 4 sides to keep it centered in the bucket. Then I'm putting wire nagers on it to loop over the holes to hold it firm to the lid(might not be necessary).

[FIGJAM]

I've never had this problem.

[unjonharley]

I've never had this problem.

My pad has been out of the bucket all year..Needs to be kept dry in OR. mold..

It has kept it's shape.. It ride to and from BM in uses.. Corning don't seem the tilt it..

[sharpstick]

orientation is not a variable. It was only long enough in one direction, unless I buy a new larger piece and start over. I am gluing poly foam wedge spacers to the cage on 4 sides to keep it centered in the bucket. Then I'm putting wire nagers on it to loop over the holes to hold it firm to the lid(might not be necessary).

correction: "wire hangers" to pull upward on the cage.

[BeeWeeDee]

Sorry Emilie, but it won't be very efficient, and if it works at all it will go through ice like crazy.

This got my mind humming.... how much ice would it take to obtain the equivalent amount of cooling from a FigJammer??

@ 45 F the Hvap = 1068.2 Btu/lb water

and searching this thread I found a conservative water consumption rate of 2 gal/ 5 hr = 3.3 lb water/hr

That rates the FigJammer at 3550 Btu/hr


Back in the day when ice was used in refrigerators (ice boxes) and today as a holdover when chillers are rated in "Tons" ... One ton of ice melting in 24 hours provides 12000 Btu/hr per ton of ice.

I finally arrive at 0.3 ton of ice is the equivalent of a FigJammer or 600 lbs - That would certainly make a lot of margaritas

[FIGJAM]

Ice is for beer!!!

THEN you can use the melt for the cooler.

[car2roll]

I've been lurking in this forum topic for a few weeks. Found all the info to build a unicooler with no questions asked.
See pictures below. How'ed I do Figjam?


Figjam unicooler swamp cooler. by car2roll, on Flickr


Figjam unicooler swamp cooler. by car2roll, on Flickr


Figjam unicooler swamp cooler. by car2roll, on Flickr


Figjam unicooler swamp cooler. by car2roll, on Flickr

[The Rod]

Had a FG cooler last year for the first time. Game changer.

Just about everyday we'd wake up to a dry bucket blowing hot air into our tent. This year I am thinking of adding a float valve and reservoir. Has anyone else done this? I am looking for suggestions and tips.


Thanks!

[sharpstick]

Put a second bucket next to it with a hose(about 3/8") arching over from one to the other. (no holes, just fill with water and it will siphon over. doubles your capacity. or add a third . . .
also most pumps will burn up if you run them dry.

[oly14]

Very nice car2roll. I built a bucket cooler last year and I'm going to build a unicooler this year. I have a larger space to cool and don't want to push it with the bucket cooler.