cooling your tent or van

[bhearn]

It's done!!! And... I *think* it works? The air feels cool/cold, but the thermometer says it's only dropping from 74.8°, 61% RH to 69.2°, 78.1% RH, even with the fan on high. Is that because the air is not dry enough? Or do I have a problem?



It's hard to know if I have it sealed well enough. Because the Genuine Joe walls are not vertical (or even straight), the Duracool is hung from an internal framework:



I have weatherstripping everywhere I think air could go where it shouldn't. The lid is just plywood, but I think that should be good enough:



At the moment I only have holes in the back:



I *think* that should be enough, because the air can easily get to the sides inside the can. I'm tempted to cut more holes in the side anyway, but then that will restrict it to outside-yurt use only; at the moment I can choose inside or outside.

Other notes: the fact that there's a discontinuity in the slope is really annoying. I addressed it by siliconing the top half of the fan, and weatherstripping the bottom:



Again, I *think* that's good enough.

Should I be getting cooler air than this? Any thoughts or tips on how to diagnose problems?

[FIGJAM]

My pads do not touch the sides.

It says that if you make the pad tube the same size as the bottom of the bucket, the slight tapper of the bucket will have the pad a 1/4" away at hole height.

Original bucket used for 7 years without a failure or changing pads.

Thus....

397648868.jpg

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397648283.jpg

[herpderpleton]

I've scoured the interwebs and this thread quite a bit but I'm running out of time and need a shortcut to a quick answer; what size inner diameter tubing and outer diameter tubing should i be looking for for my basic figjam design (and also subsequent Tee)?

I believe i'll be using this pump, unless someone has a better suggestion from amazon:

amazon.com/dp/B010LY7P3Y/_encoding=UTF8?coliid=I3Q5SBCE39MS7X&colid=1WKF8O7HH0BNJ

Thank you very much in advance!

[bjorken]

I'm having trouble with my swamp cooler and was hoping someone here might have pointers. Thanks to Figjam and all the others for their support here...

Anyway, last year my fan was under-powered and was very disappointing. Since I have access to a genny I decided to go with 120v and upgrade to a strong fan. One of these: 12" fan. Because it was too big for the bucket I used metal sheeting to "connect" the fan to the bucket, as shown in the picture below. Issue now is that NO air is coming through the small duct. I'm wondering if the lower/side panel of the fan needs to stay uncovered, and that's why it's not putting out any air. However, if I uncover this panel the air won't be forced to flow through the pads.

Picture of current setup:

Any thoughts all?

[Canoe]

Many thoughts.
What was your setup? Was there sufficient exhaust for the structure so it could allow the swampcooler to blow air inside it?
On the hole visible on the right, your pad appears to be against the hole. Read the post two up on this page regarding that issue. and this one viewtopic.php?f=280&t=33842&start=3930#p1143819
That fan is for blowing air in an open space. Not for creating pressure/vacuum, which sucks air in the holes and through the wetted pads.
You've constricted what flow it can create.
If you do manage to get a fast flow, it may move air through the pad too fast, and you'll get dry spots and pass hot air through.
The size of the holes will limit how fast/much air can move through them.

So the pad is positioned wrong (which would limit air flow even with a correct fan) and the new fan is mismatched to the job. Assuming you still have the original fan, and it is one of the recommended fans, then the setup was suspect (exhaust, duct, power,).

Given the new fan has a constricted input and a constricted output and isn't for building pressure but blowing, it's likely spinning away (but constricted) circulating air past the ends of the blades like a doughnut of air.

[EGAZ]

bjorken: Well that much restriction is not going to work. Dump the 12" fan and g0 back to the 200CFM 12VDC fan specd.

Like Canoe said you had other problems as too many have no issue with the cooler as is.

herpderpleton: Your link is broken.... The tubing/tee is the same size as the pump barbs, usually 1/4 or 5/16" ID. OD can be anything.

[Canoe]

And read this one
viewtopic.php?f=280&t=33842&start=3840#p1138440

[bhearn]

Bump... help? I head out for Reno on Wed. Need to get the cooler in playa shape tomorrow. Thanks for any insight.

It's done!!! And... I *think* it works? The air feels cool/cold, but the thermometer says it's only dropping from 74.8°, 61% RH to 69.2°, 78.1% RH, even with the fan on high. Is that because the air is not dry enough? Or do I have a problem? ...

Should I be getting cooler air than this? Any thoughts or tips on how to diagnose problems?

[Canoe]

Bump... help? I head out for Reno on Wed. Need to get the cooler in playa shape tomorrow. Thanks for any insight.

It's done!!! And... I *think* it works? The air feels cool/cold, but the thermometer says it's only dropping from 74.8°, 61% RH to 69.2°, 78.1% RH, even with the fan on high. Is that because the air is not dry enough? Or do I have a problem? ...
Should I be getting cooler air than this? Any thoughts or tips on how to diagnose problems?

I've got one low res evaporative cooling chart. According to it, you're showing around 1/2 the drop you'd expect (~9F).
At playa humidity & temps, you should get more of a drop, but it appears there are issues.

Figjam has already pointed out the need to have the pads away from the sides/holes. Your photos show the pads close or at the holes.

To maximize the airflow getting to all of the pad, hence spreading the airflow over all of the available pad (which also increases the dwell time of the air within the pad...), I'd cut a half-inch, maybe an inch, off of the ends of your PVC distribution bar, so the pad is away from the holes. And it looks like you'd benefit from having the front bar cut down the same on each end, to bring the pads away from the short sides of the box.

Is that weather stripping still have the paper on the adhesive? Poor seal if it does.
To test for leaks, with the fan on, wet your finger and hold it near the lid edge to feel air flow where it shouldn't be. Or borrow someone's e-cigarette and see if the vapour is sucked in around the lid.

[bhearn]

I've got one low res evaporative cooling chart. According to it, you're showing around 1/2 the drop you'd expect (~9F).
At playa humidity & temps, you should get more of a drop, but it appears there are issues.

Figjam has already pointed out the need to have the pads away from the sides/holes. Your photos show the pads close or at the holes.

Thanks, very useful info re the chart. Was Figjam's comment for me? Apologies, I thought that was following up on a bucket question. My pads do not touch the sides (consistent with that, water does not leak out the holes). But I will see whether I can pull them a little farther away.

Another thing I noticed is that Figjam's holes in the tubing for the bucket cooler are the size of gauge 10 wire... mine are smaller. Water flow looked fine before I attached the pads, though.

To maximize the airflow getting to all of the pad, hence spreading the airflow over all of the available pad (which also increases the dwell time of the air within the pad...), I'd cut a half-inch, maybe an inch, off of the ends of your PVC distribution bar, so the pad is away from the holes. And it looks like you'd benefit from having the front bar cut down the same on each end, to bring the pads away from the short sides of the box.

Is that weather stripping still have the paper on the adhesive? Poor seal if it does.
To test for leaks, with the fan on, wet your finger and hold it near the lid edge to feel air flow where it shouldn't be. Or borrow someone's e-cigarette and see if the vapour is sucked in around the lid.

Thank you, will follow up with results tomorrow! Yes, I did realize I'd neglected to remove the paper backing, so that's the first thing.

About the lid, though, I realized that air getting in there is not actually an issue -- it's no different from air coming in the holes. So the weather stripping at the lip now seems pointless. It's the seal on top of the PVC that counts. I can't see an easy way to test for a good seal there, though.

[pterodactyl]

If I use a 240 CFM fan would that be too much air for the bucket method? It's all the local store had. This is it.

Maybe add more padding to offset the increased air flow?

Thanks for the help.

[Canoe]

You need to pay attention to the details...

My pads do not touch the sides (consistent with that, water does not leak out the holes). But I will see whether I can pull them a little farther away.

THE GAP IS AN ESSENTIAL COMPONENT
The gap provides ample air flow distributed inside the container to all of the pad area to meet the demand of the negative air pressure on the other side of the pad that sucks the airflow through the pad. Your pads are way too close to the sides. Fix it, or have limited performance as you're using a limited area of the pads. On the playa, without distributed air flow you may dry out the pad near the holes and pass hot dry dusty air to your interior.

Another thing I noticed is that Figjam's holes in the tubing for the bucket cooler are the size of gauge 10 wire... mine are smaller. Water flow looked fine before I attached the pads, though.

There has to be enough water flow to keep the pads wet with the airflow in dry playa air. Check what the design uses.

About the lid, though, I realized that air getting in there is not actually an issue -- it's no different from air coming in the holes. So the weather stripping at the lip now seems pointless. It's the seal on top of the PVC that counts. I can't see an easy way to test for a good seal there, though.

The lid is an issue if you run the unit inside a structure, which I believe you said was an option.
And your lid above the fan is a short-circuit to the negative pressure volume on the "inside" of the pads.
The air flow being pulled out of the box needs to come only from through the wet pad.

[Canoe]

If I use a 240 CFM fan would that be too much air for the bucket method? It's all the local store had. This is it.
Maybe add more padding to offset the increased air flow?
Thanks for the help.

It's not the CFM as much as it is the pressure the fan builds for sucking air through the pads. For some reason I can't see the fan specs on that site.
Find the specs for one of the fans that figjam has recommended (preferably near the end of the thread) and compare that to what you see on that site, or find that fan on a site that provides full specs.

[bhearn]

You need to pay attention to the details...

I've read this whole thread, but my cooler has issues, so fair enough...

THE GAP IS AN ESSENTIAL COMPONENT
The gap provides ample air flow distributed inside the container to all of the pad area to meet the demand of the negative air pressure on the other side of the pad that sucks the airflow through the pad. Your pads are way too close to the sides.

This is what it looks like from above. I was careful to add that spacer to keep the main pad area away from the side.

The lid is an issue if you run the unit inside a structure, which I believe you said was an option.

Good point. My current plan is to have it outside; I just wanted to keep my options open.

[Canoe]

Not enough gap.
"Not touching" is not good enough.
You've got the higher airflow of an Endless Breeze too.

not enough gap.jpg

Lid seal within the red box is a short circuit of air from outside the box to the negative pressure volume on the "inside" of the pad.

inside.JPG

[Canoe]

And it appears that there's a good chance you've got an air path through the pads at their end that is dry.
Cut the end caps off, add a 90 and extend over the corner of the pad to ensure there's no dry pad path.
That will also pull the front of the pad away from the holes to make an adequate gap.

inside dry pad.jpg

So you've got to look at:

• inadequate gap,
• dry corners at the end,
• possible leak past the lid to the interior negative pressure volume.

[bhearn]

Thank you. I think the front lip seal is good, but will check. Good idea on the end caps. I was careful to extend the pad there to avoid a gap, but you're right, better if it's wet. The gap still looks sufficient to me at the top, but maybe is it not. I can keep the material from puckering out below with some internal wire support, perhaps. If not, yes, I'll cut the pipes down. (I'm not looking forward to re-hanging the pads, though -- not sure I have time.)

But, the first thing is just to remove the paper backing on the top seal!

[herpderpleton]

bjorken: Well that much restriction is not going to work. Dump the 12" fan and g0 back to the 200CFM 12VDC fan specd.

Like Canoe said you had other problems as too many have no issue with the cooler as is.

herpderpleton: Your link is broken.... The tubing/tee is the same size as the pump barbs, usually 1/4 or 5/16" ID. OD can be anything.

Yea, for some reason i found amazon links dont show up or are just formatted weird. I assumed i could remove the 'http://www.' part and people would figure it out.

[Canoe]

Good idea on the end caps. I was careful to extend the pad there to avoid a gap, but you're right, better if it's wet.

Fault is at the corner (orange).
Path is within the red.

inside dry pad.jpg

The gap still looks sufficient to me at the top, but maybe is it not. I can keep the material from puckering out below with some internal wire support, perhaps.

That might work with the fan on low. But due to using a limited area of the pad, it won't cool as well as a bucket cooler. And it may dry out inline with the holes and pass hot dusty air to your interior...

Think of it as 1/2 of those holes feed the front pad area, 1/4 the pad area on the right side, 1/4 the pad area on the left side. The air going in those holes needs an easy path to get to the sides and far corner of the box, so it can provide an even air response to the negative pressure on the inside of the pad, so the airflow through the pad is distributed reasonably evenly so all of the pad is working.

The number and size of the holes is perfectly adequate to the task. The air path inside the box before the pads is not. Increasing the gap provides that interior path.

[bhearn]

That might work with the fan on low. But due to using a limited area of the pad, it won't cool as well as a bucket cooler.

I'm not following this... what do you mean by a limited area of the pad? In principle, shouldn't this cool much more than a bucket cooler? Otherwise I'd just have built a bucket cooler. But apparently they are insufficient for yurts.

[Canoe]

That might work with the fan on low. But due to using a limited area of the pad, it won't cool as well as a bucket cooler.

I'm not following this... what do you mean by a limited area of the pad? In principle, shouldn't this cool much more than a bucket cooler? Otherwise I'd just have built a bucket cooler. But apparently they are insufficient for yurts.

In principle yes. In practice yes, IF you build it with the details that let it work.

Without an adequate air path on the inside of the container for the air to get to the sides and far corners (re-read my last post), the bulk of the airflow through the holes will be through the pad inline with the holes (plus a bit). So only part of your pad area is in play (less than a properly built bucket cooler), and it's less productive as that air flow is at a higher velocity resulting in less dwell time. This will be worse with higher fan settings. And more likely to get those overused inline areas becoming dry and passing hot dusty air...

You need more gap so that once the air is through the holes it has an easy path to get to all areas of the pad.

Then you have the full pad area working, and as the air volume/velocity through the holes is distributed to the whole pad, the resulting air velocity through the pad is reduced for more dwell time to the surface area of the water on the pad, so you maximize the evaporative cooling.

Maximized pad area in play, and it has the greatest dwell time possible for the fan setting.

[bhearn]

Gotcha. Will report back.

[Canoe]

Plus addressing other details, like dry path at the corners and possible leak into the negative pressure volume.

So just cut the end caps off, 90 degree plus an inch, with watering holes, with enough cut off to give a healthy gap at the front between the pad and the side. You need a healthy gap on the short sides too. Then check the seal along that lip of the lid.

[pterodactyl]

If I use a 240 CFM fan would that be too much air for the bucket method? It's all the local store had. This is it.
Maybe add more padding to offset the increased air flow?
Thanks for the help.

It's not the CFM as much as it is the pressure the fan builds for sucking air through the pads. For some reason I can't see the fan specs on that site.
Find the specs for one of the fans that figjam has recommended (preferably near the end of the thread) and compare that to what you see on that site, or find that fan on a site that provides full specs.

Didn't realize the specs were missing there. Here is another link that shows the specs. It's the same brand as the recommended fan, but the next size up I guess. I'm not sure what specific specs to compare aside from CFM. Any advice? Thanks again for the help.

[Canoe]

Didn't realize the specs were missing there. Here is another link that shows the specs. It's the same brand as the recommended fan, but the next size up I guess. I'm not sure what specific specs to compare aside from CFM. Any advice? Thanks again for the help.

I'm having internet issues, but it looks like my connection is letting me get a quick post in.
The original fan vs the one you specified.

• AFB1212SHE-CF00 190 cfm, 17.74 mm H2O, 1.6 A, 55.5 dBA, 4100 rpm
• AFB1212GHE-CF00 240 cfm, 27.48 mm H2O (22), 3.24 A (2.45), 66 dBA, 5200 rpm

So the GHE looks like figjam's original SHE, but on steroids: more pressure, more cfm, more noise and - more amps.

I don't know if the GHE version will move more air through the pad than the pump can keep water supplied to the pads.

In Jan 2017, figjam is still recommending the SHE version. viewtopic.php?f=280&t=33842&hilit=AFB12 ... 0#p1129028

My searching isn't finding anyone reporting on their results with the GHE version. You may have better luck.

I'd suggest:

• quote the specs above and include your pump & its specs, power source (12 VDC or lower VDC from solar, etc.) (and using duracool pad?) and hope someone chimes in on: if it should work, or did it work in their setup, or
• the GHE certainly has the pressure: get a fan speed controller so you can tame the fan down if it's overpowering your setup and drying out the pad.

Hint: I assume you've got adequate spacing between the pads and the side of the bucket, so the air flow will be distributed to all of the pad area.

(post on SHE, EHE, GHE viewtopic.php?t=33842&start=1440#p859717)

(For comparison, the Endless Breeze on low is ~250 CFM and draws from 1 to 1.5 A depending on who/what is measuring. On high, it's 900 CFM at 2.29 to 3 A)

[pterodactyl]

Didn't realize the specs were missing there. Here is another link that shows the specs. It's the same brand as the recommended fan, but the next size up I guess. I'm not sure what specific specs to compare aside from CFM. Any advice? Thanks again for the help.

I'm having internet issues, but it looks like my connection is letting me get a quick post in.
The original fan vs the one you specified.

• AFB1212SHE-CF00 190 cfm, 17.74 mm H2O, 1.6 A, 55.5 dBA, 4100 rpm
• AFB1212GHE-CF00 240 cfm, 27.48 mm H2O (22), 3.24 A (2.45), 66 dBA, 5200 rpm

So the GHE looks like figjam's original SHE, but on steroids: more pressure, more cfm, more noise and - more amps.

I don't know if the GHE version will move more air through the pad than the pump can keep water supplied to the pads.

In Jan 2017, figjam is still recommending the SHE version. viewtopic.php?f=280&t=33842&hilit=AFB12 ... 0#p1129028

My searching isn't finding anyone reporting on their results with the GHE version. You may have better luck.

I'd suggest:

• quote the specs above and include your pump & its specs, power source (12 VDC or lower VDC from solar, etc.) (and using duracool pad?) and hope someone chimes in on: if it should work, or did it work in their setup, or
• the GHE certainly has the pressure: get a fan speed controller so you can tame the fan down if it's overpowering your setup and drying out the pad.

Hint: I assume you've got adequate spacing between the pads and the side of the bucket, so the air flow will be distributed to all of the pad area.

(post on SHE, EHE, GHE viewtopic.php?t=33842&start=1440#p859717)

(For comparison, the Endless Breeze on low is ~250 CFM and draws from 1 to 1.5 A depending on who/what is measuring. On high, it's 900 CFM at 2.29 to 3 A)

I'm pretty sure the pump I'm using is beefier than the recommended one also so hopefully it'll work. I have to pack it on the truck tonight and have a million other things to do so I'm just going to bring it out and hope it works. The pads seemed to be staying wet when I tried it last night. I just wasn't sure if more cooling pads would be a good idea or not. I do have them away from the bucket walls per recommendations here. I appreciate all of the help.

[herpderpleton]

Following up previous question and thanks again for your input. I'm trying to do a basic figjam build. This just arrived from amazon. Is this pump too small or not powerful enough?

https://www.amazon.com/gp/product/B010L ... UTF8&psc=1

pump.jpg

[spacetime]

That is the size I use and have a backup for. Try it, should be plenty of drips

[herpderpleton]

That is the size I use and have a backup for. Try it, should be plenty of drips

Nice. Thank you kindly, spacetime!

[FIGJAM]

That's why we use a return air register instead of holes for the unicooler.

It keeps the water flowing to the inside while providing max air flow.

It looks like you will have air flowing OVER your pvc which will Not let the cooler work at its best.

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403577512.jpg