cooling your tent or van

[mooserider]

How big is the dryer vent?

The washer/dryer has a 3-inch diameter vent hose that was hose-clamped to the inside of the vent. I can see the outside ground peering into the inside end of the vent, so there are no obstructions in the vent cap itself, just a right-angle bend (same as on a house) to keep rain from pouring in.

The air has to flow freely through the pad.

I was planning on stuffing a shop rag into the vent to keep the vehicle from filling up with road dust, but if I can get a practical use out of the vent....

[Canoe]

The washer/dryer has a 3-inch diameter vent hose...

(hoping I did the math right)
Endless Breeze is 12" diameter, for 113 area, less a center of 4" for 12.47, call it a net of 100 sq.in. that it moves air through (ignoring the grill).
The 3" duct's area is 7.07 sq.in..
That's more than a ten times difference.

EB's CFMs are around 250, 500, 900 cfm.
250 CFM in:

• 3" duct needs 5092.96 ft/min, or 84.8 ft/s.
• 6" duct needs 1273.24 ft/min, 21.22 ft/s.
• 10" duct needs 458.37 ft/min, 7.64 ft/s.
• 12" duct needs 318.31 ft/min, 5.31 ft/s.

250 CFM through 10" x 10" (100 sq.in.) would be at 360 ft/min, 6 ft/s.
500 CFM, 720 ft/min and 12 ft/s.
900 CFM, 1296 ft/min and 21.6 ft/s.
Through a box-cooler's three vent/pad of 10x10, they drop to 1/3 velocity. For a much nicer dwell time for the hot air in the irrigated pad. Speed through the pad is of course faster due to the reduce area of the paths through the pad, but you can see the relative differences.

I don't see much hope for a 3" duct supplying enough air to allow a swamp-cooler to cool an RV.

[mooserider]

I don't see much hope for a 3" duct supplying enough air to allow a swamp-cooler to cool an RV.

Drat. Although I wasn't planning on shrinking the actual cooler (wet pad area) down, so with a sufficiently strong intake fan on high, wouldn't it still be able to suck a decent amount of air in (even if the outside vent acts like a vacuum cleaner)?

[FIGJAM]

It can if the fan can create enough "static pressure".

The fans I've tested in these designs have to breath freely.

You might look up "bilge exhaust fans" as an example.

Even here I'm not finding something that will get up to 900 CFM.

http://www.ebay.com/bhp/bilge-blower

[FIGJAM]

Is the washer/dryer space against an outside wall?

You may be able to have an 2'x2' RV hatch installed to access that space for an intake for the cooler.

[mooserider]

I don't really want to saw a hole in the side of the RV without overwhelming good reason. If I sell this vehicle, I'll need to put the washer/dryer back in there (hopefully I can fix it at cheaper than totally replacing the whole unit). Isn't the fan in your design after the wet pads? If so, I could use a larger bilge fan there, and just use a short rigid duct from the vent to the cooler (and seal the cooler so air doesn't leak into it from the vehicle interior rather than through the duct). Seems like I'd want to do that anyway to reduce the amount of dust collected on the fan.

[LowePro]

Apav--that 3" duct line is likely too small, it would choke or constrict the air flow too much and your swamp cooler would not have adequate air flow to be very effective. (In my educated amateur opinion anyway).

Yes the fan is "after" the blue cooler pad so the blue pads filter the airflow pretty well, without any additional air filter.

If you scale up to a more powerful fan, please let us know how it works out.
(Just another alternative to consider--if your RV has a window that easily pops out, you can use this opening for your swamp-cooler. Pop out the window, cut a piece of plywood or Rmax insulation board to fit into the window opening, and then cut a circular hole in that board that fits the swamp cooler fan. )_

[FIGJAM]

If you have a big sliding window, you can remove just the screen for that window and replace it with a piece of cardboard.

Then cut your hole in that for the cooler intake.

[ShreddinPB]

I build my boxes out of plywood.

I've used an 80 gph on my box design and it was plenty, but yours is bigger and taller, so more is better.

This one should be more than enough.

http://www.amazon.com/Rule-24-Marine-36 ... B000O8D8QG

So, I happened to have a couple sheets of 12"x24" ABS at the house for another project, and looking at it, it looks like it might be on the small side? It would roughly be the same size as a bucket cooler. Should I increase the size of the sheets?
Or is the fact that I would have 4 large pads what makes this work cooler than a standard bucket?

[FIGJAM]

You'll need bigger than that jut to accommodate the vent panels inside the cooler, and you'll want it taller for enough water to last 8 hrs.

On a side note, the first box cooler I built out of FRP and plastic molding strips, glued together with E6000.

Similar to this, but a box.

[reggie13]

ok, I'm almost to the point of connecting everything but i have 2 questions......I have provided a VERY basic schematic (don't laugh! ) my questions are, how exactly do i connect the wires to the battery? just connect the wires to battery clamps? if so, do you solder them to the clamp? i'm using the battery for both, as i don't want to take a chance on the solar option for the fan. secondly, is it correct to run the pump wires between the bucket and the padding and out thru the top, or next to padding and out one of the holes?

thanks!
Reggie

hook up.png

[Jackass]

The pump and the fan will each need a positive and a negative from your battery, how you make that happen and where you make the splice doesn't really matter as long as both units get both positive and negative from your battery.

Your wires over the battery with question marks is a direct short. The only thing that will happen there is mass smoke and a glowing hot wire, melting anything in its path. It's kinda like a fundamentals of welding beginner course...

[reggie13]

The pump and the fan will each need a positive and a negative from your battery, how you make that happen and where you make the splice doesn't really matter as long as both units get both positive and negative from your battery.

so after my splice, the main wire to the battery will have positive and negative. when i split that wire, i attach pos to pos post and neg to neg post, right? my issue is HOW to attach them to the posts.

please correct me if i'm wrong...don't want to blow this thing up! lol

thanks!
Reggie

[Jackass]

Positive from battery- positive on fan, positive on pump.

Negative from battery- negative on fan negative on pump.

Since it quite a low-draw circuit you could just strip the wire off about the last 6in, wrap it around battery terminals, put a binder clip holding the winding.

Just don't let the two terminals on your battery make contact with each others potential.

[reggie13]

Positive from battery- positive on fan, positive on pump.

Negative from battery- negative on fan negative on pump.

Since it quite a low-draw circuit you could just strip the wire off about the last 6in, wrap it around battery terminals, put a binder clip holding the winding.

Just don't let the two terminals on your battery make contact with each others potential.

Gotcha! and just to make sure.....can anyone verify i'm on the right track here? i'm more visual than technical, so bear with me! (the green box is the splice)

thanks!
Reggie

g4265.png

[Popeye]

What Jackass said, but if you want somethinjg a little more substantial than a binder clip, your local auto or boat store probably has something like this:
http://www.c-mesales.com/contents/media ... ochure.jpg assuming you have wing nuts already on the terminals. If not then add this http://www.wiringproducts.com/contents/ ... rminal.jpg
If you are wrapping around a screw twist the wire first then wrap clockwise a little more than 2/3 rds and tighten.
Largish alligator clips like on a battery charger will work too.

Edit to add clockwise

[Jackass]

Now you're getting somewhere.

You could also run each one individually, so that you could use the fan by itself or turn the pump on first in order to pre-charge the pad with water before drawing air...It gives the cooler a nice, impressive start.

[reggie13]

What Jackass said, but if you want somethinjg a little more substantial than a binder clip, your local auto or boat store probably has something like this:
http://www.c-mesales.com/contents/media ... ochure.jpg assuming you have wing nuts already on the terminals. If not then add this http://www.wiringproducts.com/contents/ ... rminal.jpg
If you are wrapping around a screw twist the wire first then wrap clockwise a little more than 2/3 rds and tighten.
Largish alligator clips like on a battery charger will work too.

Edit to add clockwise

Thanks Ulisse! that helps a LOT! i appreciate the pics too! lol now as long as i have the wiring right, i should be good to go!

Reggie

[reggie13]

Now you're getting somewhere.

You could also run each one individually, so that you could use the fan by itself or turn the pump on first in order to pre-charge the pad with water before drawing air...It gives the cooler a nice, impressive start.

Um...ok....that makes sense.....but are we now talking about putting switches INLINE, before the splice? and what kind of switch?

and then i'd have 2 sets of wires on each post, yes?

i will be the proudest SOB on Earth if/when I can get this to work! lol

Reggie

[FIGJAM]

[reggie13]

thank you FIGJAM!

am i correct in that the pump and fan are wired together? and what kind of connection cable is that so i know what to look for?

thanks,
Reggie

[Jackass]

Now you're getting somewhere.

You could also run each one individually, so that you could use the fan by itself or turn the pump on first in order to pre-charge the pad with water before drawing air...It gives the cooler a nice, impressive start.

Um...ok....that makes sense.....but are we now talking about putting switches INLINE, before the splice? and what kind of switch?

and then i'd have 2 sets of wires on each post, yes?

i will be the proudest SOB on Earth if/when I can get this to work! lol

Reggie

You could do switches inline or just have two wires on one post of the battery.

Or what Mr. Jam suggests, our very own resident playa contraptioneer.

[oscillator]

OK, I am going to revisit this situation.

Find it hard to believe 4 of 4 unit failures, when no-one else has reported probs w/ these same units.

Maybe I am doin it wrong????

Q: for those that have used these same pumps - is there any prep necessary? Some sekret decoder ring??

There were no instructions, no markings to what was input and output, I tried both ways, submerged, the pumps activate, just no hot monkey-love pumpin thru-put action.

ALSO: any other recommendations for a RELIABLE 12VDC pump that can feed a 190 CFM fan????

in dust,

-OSC

Quick report on my experience:

Ordered (4) units. Of those four, guess how many worked?

Nada. Zip.

The motor turns on, emitting something much less than an "ultra quiet" noise, but I got no flow at all thru the unmarked inlet or outlets - in either direction.

P1000652.JPG

P1000653.JPG

Perhaps I am doing it wrong, but methinks you get what you pay for.

BTW, the previous $45 pump died after 3 days on playa after a grand total of maybe 12 hours usage.

-OSC

This is the new "best choice" that I've found at a fraction of the cost of the original!!!

http://www.ebay.com/itm/like/261351083541?lpid=82

[FIGJAM]

When I first bought these pumps 5 years ago, they were $14.95.

They are now $44.99.

The two originals that I bought are still working. (one in the original bucket cooler and one in the unicooler in the playapod)

People were looking for something cheaper, so I found the "other" pumps.

I built a couple of coolers and the new cheap pumps work fine.

http://www.ebay.com/itm/12VOLT-DC-SUBME ... 0684927203

The fan is spliced into the 15' wire that came on the "pricey" pump.

[LowePro]

I use that E-auction pump as well. Has lasted 2 burns so far. I bought an extra to keep in my kit since they are so darn cheap. I actually ran iced tea thru my swampie one day because the tea jug sprang a leak faster than we could drink it--still no problems w/ the pump!
(The shipping is super slow so order it NOW)

Don't let the pump run dry, and if the swamp-water gets too dusty/muddy, dump it out and start over with clean h20. When I first built the cooler, a lot of little specks of PVC from the drilling and blue lint from the duracool pad appeared in the swamp water. Suggest (at home) rinsing the bucket and pad really well with a hose sprayer to blast out the bits and keep from clogging the pump.

[Popeye]

Seems like the only things in common with the 4 pumps is the manufactuirer and the battery. Might check voltage.

OK, I am going to revisit this situation.

Find it hard to believe 4 of 4 unit failures, when no-one else has reported probs w/ these same units.

Maybe I am doin it wrong????

Q: for those that have used these same pumps - is there any prep necessary? Some sekret decoder ring??

There were no instructions, no markings to what was input and output, I tried both ways, submerged, the pumps activate, just no hot monkey-love pumpin thru-put action.

ALSO: any other recommendations for a RELIABLE 12VDC pump that can feed a 190 CFM fan????

in dust,

-OSC

Quick report on my experience:

Ordered (4) units. Of those four, guess how many worked?

Nada. Zip.

The motor turns on, emitting something much less than an "ultra quiet" noise, but I got no flow at all thru the unmarked inlet or outlets - in either direction.

P1000652.JPG

P1000653.JPG

Perhaps I am doing it wrong, but methinks you get what you pay for.

BTW, the previous $45 pump died after 3 days on playa after a grand total of maybe 12 hours usage.

-OSC

This is the new "best choice" that I've found at a fraction of the cost of the original!!!

http://www.ebay.com/itm/like/261351083541?lpid=82

[oscillator]

Ah - just to be clear, am now using these little pumps:

http://www.ebay.com/itm/like/261351083541?lpid=82

Four out of four failed, meaning they turn on, I can hear the motor buzzing, but there is no thru-put when submerged. No suction as Mr Dyson would say.

I've def powered with charged 12V battery and tried a 12VDC 5a regulated power supply.

Q: is there any prep these little guys need? Baffles removed or otherwise?? (grasping at straws here)

Any other recommendations for suitable 12VDC pump?

tia,

-OSC

[FIGJAM]

I didn't have to do anything special for the cheap pumps.

When I first bought these pumps 5 years ago, they were $14.95.

They are now $44.99.

The two originals that I bought are still working. (one in the original bucket cooler and one in the unicooler in the playapod)

People were looking for something cheaper, so I found the "other" pumps.

I built a couple of coolers and the new cheap pumps work fine.

These are the pricier pumps that have lasted 5 years so far.

http://www.ebay.com/itm/12VOLT-DC-SUBME ... 0684927203

The fan is spliced into the 15' wire that came on the "pricey" pump.

[LowePro]

Bummer! You've probably tried this, but if not,- reverse the black / red connection to your battery? Maybe the pump got wired wrong at the factory.
The output should be the top tube fyi.

[Popeye]

At this point, if they where my pumps I would take one apart- even if it meant breaking/ cutting it open. It's making noise so the motor is probably turning. Check that the impeller is tight to the shaft and the shaft is not broken. Make sure there is an impeller and the casting or whatever where the water comes in and out inside the pump is open. I'd expect that if you blow into the intake you won't get a lot of air coming out the outlet. If there is a lot of air coming out then it is bypassing the impeller and the impeller could be turning without pushing water through. In other words the impeller is to small for the casting/pump body.