cooling your tent or van

[FIGJAM]

That is what I would have suggested, but did'nt want suggest a permanent change to the trailer.

Have you considered a small RV hatch?

Something like this.

http://www.campingworld.com/shopping/it ... inch/49567

[Canoe]

swamp-cooler for pickup camper

NOTE: this is a side track. Not applicable to the huge majority of swamp-cooler setups.

> First off, I don't think that the bucket will fit underneath the bench hole.
Too bad.

> the cold air would come in low and push out the hot air from the window above slowly filling the camper with cold air from the bottom up.
That's exactly it!

> I'd like to stick with the bucket design because I still do a fair amount of tent camping at music festivals and otherwise) then I'm liking the idea of putting the bucket inside a box IN the camper.
> I think the box with bucket inside would fit on the floor between the the benches ... underneath the table ... duct the outside air into the box through one of the bench holes...

Sounds good. Easy to secure there for traveling too.

There is a choice between sitting on top of the bench vs. sitting down on the floor - the height that the fan will be pushing the heavier cool air up. Sitting on the floor (and if under the bench), it will have more of a lift to push the air all the way up. Not an issue when the top is down and it's going out an upper window. With the top up, it's got that extra height to lift the cool air to fill the space and get it out the vinyl window. With the fan on the bench, the lift height is less. That's a major reason why you don't want the swamp-cooler sitting outside on the ground in high shelters.

I'd go for having it on the floor between the benches, with your knowing that you might have to set it up on the bench should that lift prove too much for the fan.

Certainly have it down between the benches for traveling to BRC.
Understand that with this setup inside the camper, you can run it while sitting on the playa in line for Gate or Exodus - for cooling the cab on 12 VDC while the engine is off...
Just run a hose to the cab (no need to pre-cool the whole camper space - swamp-cooler should take care of that quickly once you're at your camp site).

> The intake ducting would only need as much area and the total area the holes in the bucket provide, right?

Easier than that. Slightly bigger than the output duct. If it's six inch output, go for eight inch input. (so one bench hole is fine)

A single flexible duct will have less resistance than a series of 90 degree angles. And if you have to lift the box up onto the bench, or otherwise reposition it, you're just flexing a hose, not trying to re-plumb hard fittings.

> some sort of plastic storage tote would work as an easy prefab box to contain the bucket.

Anything rigid, sealable to the intake duct, sealable to the bucket output duct and with a rigid sealable lid. Note that the box will be under vacuum pressure from the swamp-cooler fan so everything MUST be rigid enough to resist that pressure and sealed. As much space as possible around the bucket for the air to flow easily to all the bucket holes; you want to use all of the holes/filter for air flow (one reason why a uni-cooler variation would be easier).

> the straight septic connector pointed up at the table and the table would act to deflect the air out in all directions.

If not too close to impede the output air flow and connecting a hose onto its output.

> If I wanted to pipe the air up top while sleeping then I could use some flexible drier hose.
> Is is right to assume that ... as the cool air filled the bottom and pushed hot air out the top that the cool air would eventually pool up all the way to the top? If so I'm not sure the ducting to the top would even be necessary.

You've got it right that the cool air will fill the space up from the bottom, but you've got flow issues with the bed open full, possibly significant. Having a hose that's long enough to reach means you're covered if you need to address this on the playa, instead of not getting your cooling or having to sleep below. The sleeping area could be somewhat excluded from the general rising air flow (that ends up going out the window) and only subject to eddy currents resulting in insufficient cooling in your sleeping area. You might have to plumb a portion of the swamp-cooler output all the way down to your feet so it can back-fill that area. Not the whole air flow (you don't want the air flowing from the hose to the window exhaust bypassing below), so you'd need a way to have a portion going up the hose with some still going out below.

And, IF the fan can't move the heavy cool air all the way up the total height effectively, and you don't feel like moving the swamp-cooler to the bench right now because you need to sleep, then have the whole flow go to the hose and dump out down by your feet; takes seconds to move the hose, worry about optimizing later.

> When not using the cooler I could just cap off the septic connector and no air would leak out as the cool air sinks.
Good. Not automatic, but works.
A quality flapped dryer vent is an easy way to one-way that flow (with a remote switch for the swamp-cooler routed to your bed above, you don't have to get out of the bed to cap the output to keep the cool with it off), but then you've got issues for connecting a hose. If you had such a vent with you on-playa, you could experiment.

[FIGJAM]

I still think I would hinge the back end of the benches just for storage space.

Here's another possibility.

This squarish bucket has about 3 gallon capacity and when I put it in the truck just now, it matched the hight and width of the wheel well.

It had laundry detergent in it, but you could build the bucket design with it just by changing the dimentions of the pad tube to fit.

Everything else would be the same.

May need to fill it more often.

[trance728]

I'm looking for a little guidance. I have a Chevy Suburban that we sleep in at the burn with the back end up covered by a monkey hut. I want to go the swamp cooler route this year to make things a little more comfortable. I'm not exactly sure the cubic foot measurement but I can't expect it to be a huge number. I was thinking about building the uni-cooler but is that more than is necessary or will it just make things very comfortable? Also looking for a suggestion on where to mount to cooler, would mounting it so the fan directs down through the sunroof be a good idea?

[Canoe]

...This squarish bucket has about 3 gallon capacity and when I put it in the truck just now, it matched the hight and width of the wheel well.

+++

• Then you don't have to build a swamp-cooler AND a containing box/bin (and ensure its seals work and stay working); fewer parts, costs & time!
• Fewer points of failure (you've eliminated the box and its seals) - this a huge plus.
• Need a way to secure it in place under there, but that shouldn't be too hard?
• Lower water reservoir volume?
  - Easy to run a water hose from inside the camper, sealed in place for re-filling with a funnel.
  - You can have a sealed water container inside auto-filling through that hose too (as shown earlier).
• After you run it's output coming up through the bench hatch, everything else you do can be the same as what you'd do for one in an inside box.
• You'd still have it for use elsewhere. (but if it doesn't fit up through the bench hole, you'd have to take the camper off? or lift the pump out and take the fan off through the bench hatch, and use them in a second cheap-to-build bucket/bin cooler)

Negatives:

• if the fan has difficulty lifting the air the full height, you can't raise this swamp-cooler higher.
• harder to reach to clean out any wet playa dust that may need removing,
  Worse: with the boxed version you need to break the box seals to get in to do the same (which is more of a pain and has to be resealed) (or have an access hatch in its top, which would still need to be resealed but would be less work).

Can still be run while in line to cool the cab!


Can it accommodate a similar square inches of filter area as the bucket cooler?

Will it fit up/down through the bench seat hole? You wouldn't have to get it in place before you mount the camper. Is it worth enlarging one of the bench seat holes to let this happen?

[FIGJAM]

Does the burbon have a tailgate, or doors that open out on the back?

If it has a tailgate, just set the unicooler on that.

If it has doors, you may need a tv tray or something to set it on unless it can set on the bumper.

[FIGJAM]

...This squarish bucket has about 3 gallon capacity and when I put it in the truck just now, it matched the hight and width of the wheel well.

+++

• Then you don't have to build a swamp-cooler AND a containing box/bin (and ensure its seals work and stay working); fewer parts, costs & time!
• Fewer points of failure (you've eliminated the box and its seals) - this a huge plus.
• Need a way to secure it in place under there, but that shouldn't be too hard?
• Lower water reservoir volume?
  - Easy to run a water hose from inside the camper, sealed in place for re-filling with a funnel.
  - You can have a sealed water container inside auto-filling through that hose too (as shown earlier).
• After you run it's output coming up through the bench hatch, everything else you do can be the same as what you'd do for one in an inside box.
• You'd still have it for use elsewhere. (but if it doesn't fit up through the bench hole, you'd have to take the camper off? or lift the pump out and take the fan off through the bench hatch, and use them in a second cheap-to-build bucket/bin cooler)

Negatives:

• if the fan has difficulty lifting the air the full height, you can't raise this swamp-cooler higher.
• harder to reach to clean out any wet playa dust that may need removing,
  Worse: with the boxed version you need to break the box seals to get in to do the same (which is more of a pain and has to be resealed) (or have an access hatch in its top, which would still need to be resealed but would be less work).

Can still be run while in line to cool the cab!


Can it accommodate a similar square inches of filter area as the bucket cooler?

Will it fit up/down through the bench seat hole? You wouldn't have to get it in place before you mount the camper. Is it worth enlarging one of the bench seat holes to let this happen?

Even with the 90 on mine I can feel the breeze 10 feet away on a calm day, so I think it will move the air in that small a space just fine.

If I had a camper, I would make sure I could access those spaces under the benches for storage. (that's why I mentioned hinging the benches)

I hate wasted space.

[trance728]

Does the burbon have a tailgate, or doors that open out on the back?

If it has a tailgate, just set the unicooler on that.

If it has doors, you may need a tv tray or something to set it on unless it can set on the bumper.

It has a tailgate, but we use that as our entrance and exit to the vehicle.

I had the idea of building a box with the fan at the bottom and a moat around it for the reservoir, then I could have 4 sides of vents to pull air through and it could sit on top of my roof over the sunroof. Maybe use some foam backing on the bottom surface of the cooler so it creates a seal around the opening of the sunroof.

[FIGJAM]

The unicooler should leave plenty of space for you to get in and out of the burbon.

You won't have to have the space sealed up unless theres a dust storm, so you could set it on one end of the tailgate blowing into the space and the air would travel in a U and out the other side.

The cooler is very portable and can be moved wherever you need it.

What you just descibed is known as a downdraft cooler.

It will work like a charm as long as you can get the moat not to leak.

That's why I have'nt designed one yet.

Don't let that stop you!

Take pictures, and I'll be interested in your progress.

[fresh]

Yes, but I don't use an inverter.

It's a good idea to have the inverter close to the batteries as the cables that go to a fair sized inverter are like jumper cable size.

How big is your inverter?

I have an inverter on my truck to run an electric jack hammer.

It's 3000/6000 watts and has DOUBLE cables to each terminal. ( I idle the truck when I use it or the batteries would be dead in an hour.)

Hook up the inverter to the battery.

Then clip the power strip to the battery and you should be good other than the recharge issue.

I just have a tiny one now and was lloking at making that purchase ASAP. any suggestions? I dont need that much juice. def not a jackhammer.

[trance728]

The unicooler should leave plenty of space for you to get in and out of the burbon.

You won't have to have the space sealed up unless theres a dust storm, so you could set it on one end of the tailgate blowing into the space and the air would travel in a U and out the other side.

The cooler is very portable and can be moved wherever you need it.

What you just descibed is known as a downdraft cooler.

It will work like a charm as long as you can get the moat not to leak.

That's why I have'nt designed one yet.

Don't let that stop you!

Take pictures, and I'll be interested in your progress.

So I could just build the uni-cooler box and have it sitting with the hatch fully open, that would still cool the area? I thought it had to be more of an enclosed area.

If I go the sunroof route, I would just build the box out of wood and then epoxy the inside and silicone the corners after, that would keep it water tight.

[Canoe]

I think it will move the air in that small a space just fine.
If I had a camper, I would make sure I could access those spaces under the benches for storage. (that's why I mentioned hinging the benches)

It's not moving the air that concerns me. It's the fan being able to generate enough pressure to push more cool air into the camper against the weight of the cool heavy air column above it up to the height of the exhaust window, without that reducing airflow through the swamp-cooler to the point where it's no longer effective enough for that space.
Actually, rather than relying on the photos, I should go back and read the measurements given...

Being careful to keep adequate structure, modifying the benches to have more than the 1'x1.5' bench holes, but where possible hinged to access most of their length would be nice for storage and give you the easiest access for maximizing a swamp-cooler installed there after you've got the camper onto the bed. Also means you're not fishing stuff in/out of 1'x1.5' holes.

Another benefit of a swamp-cooler NOT inside. You don't have to worry about removing its water before you drive off. Who cares if a bit splashes out onto the bed.

[Canoe]

It's not moving the air that concerns me. It's the fan being able to generate enough pressure to push more cool air into the camper against the weight of the cool heavy air column above it up to the height of the exhaust window, without that reducing airflow through the swamp-cooler to the point where it's no longer effective enough for that space.
Actually, rather than relying on the photos, I should go back and read the measurements given...

...Anyway, as for total height it is probably 7'-8' inside by the door and tapers down to about 1' at the end of the cabover. I'm 6' and can stand upright in most of the main area of the camper...

My bad.
I was fooled by how dramatic that profile looks with the raised angled roof.
It's roughly equivalent to pushing cool air into a hexayurt with eight foot high walls with an exhaust vent high on the wall, from a bucket cooler sitting on the ground outside, with an elbow on its top through the wall at just-above-bucket height.
I would still go with a flapped vent or your capping it to keep the cool air from falling out through the cooler.

[Canoe]

So I could just build the uni-cooler box and have it sitting with the hatch fully open, that would still cool the area? I thought it had to be more of an enclosed area.

>> the cold air would come in low and push out the hot air from the window above slowly filling the camper with cold air from the bottom up.
>That's exactly it!

Running into an open door, it's just a source of blowing cool air washing over you. Which is nice. But not as effective in pushing out (by replacing) any dust in the air inside the camper, and not as nice as being immersed in cool air.

If you've got a dust storm, you'll have to close the door and bake. With the bed open, will you be needing to fill the camper with cool air up to the vinyl window to get the sleeping area cool too. Perhaps an upper half-door that can sit on top of a uni-cooler to seal it? And if you want cooling while there's heavy winds, you'll have to construct that upper half-door appropriately.

But, that's fine for when you're at camp. Don't know about when you're in line on the playa if it would take the bumps while driving.

You could always add a vent hatch to one side (left on yours) of the door for a uni-cooler to blow air through, but that should be done nicely as it does alter the camper from stock for resale.

Makes between the camper and the bed look more and more attractive. And easiest to do if you modify the bench for more access.

[FIGJAM]

Trance is talking about a chevy suburban.

A cooler can work in an inclosed area with a little venting (filters dust out) or in an open space (like the burbon with the back open).

When I'm sitting in the shade of my camp on hot afternoons, my bucket cooler is sitting there blowing on me while I people watch.

Then I drag them in off the street for some "cool air in the cool chair" and give seminars! (by the time I'm finished, the less dressed are cold)

[doober831]

A quality flapped dryer vent is an easy way to one-way that flow (with a remote switch for the swamp-cooler routed to your bed above, you don't have to get out of the bed to cap the output to keep the cool with it off), but then you've got issues for connecting a hose. If you had such a vent with you on-playa, you could experiment.

I'm trying to keep this project as simple as possible. I don't expect to be turning the cooler on and off while sleeping so I wouldn't have to worry about capping it while in bed. I think I'll just cap it if I want to see how cool it stays with the cooler off while I'm hanging out during the day.

I still think I would hinge the back end of the benches just for storage space. Here's another possibility. This squarish bucket has about 3 gallon capacity and when I put it in the truck just now, it matched the hight and width of the wheel well.

The holes that are already there allow enough access to the area in front of the wheel wells and you can access the area behind the wheel wells from the tailgate (it is always down with the camper on the truck. The hinges are a bit more of a project than I care to take on, especially right now.

...This squarish bucket has about 3 gallon capacity and when I put it in the truck just now, it matched the hight and width of the wheel well.

...
[*]You'd still have it for use elsewhere. (but if it doesn't fit up through the bench hole, you'd have to take the camper off? or lift the pump out and take the fan off through the bench hatch, and use them in a second cheap-to-build bucket/bin cooler)[/list]
...[*]harder to reach to clean out any wet playa dust that may need removing...Will it fit up/down through the bench seat hole? You wouldn't have to get it in place before you mount the camper. Is it worth enlarging one of the bench seat holes to let this happen?

I'm beginning to think that having the cooler in the camper using the box might actually be more ideal than fitting in between the camper and the truck bed. The bucket, square or otherwise, would not fit through the access hole in the bench which would make accessing the cooler for anything a pain in the ass. If it's in the box in the camper I could have easy access should I need to fiddle, refill, ect.

A single flexible duct will have less resistance than a series of 90 degree angles. And if you have to lift the box up onto the bench, or otherwise reposition it, you're just flexing a hose, not trying to re-plumb hard fittings.

> some sort of plastic storage tote would work as an easy prefab box to contain the bucket.

Anything rigid, sealable to the intake duct, sealable to the bucket output duct and with a rigid sealable lid. Note that the box will be under vacuum pressure from the swamp-cooler fan so everything MUST be rigid enough to resist that pressure and sealed. As much space as possible around the bucket for the air to flow easily to all the bucket holes; you want to use all of the holes/filter for air flow (one reason why a uni-cooler variation would be easier).

If I found a box that sat 6"-8" higher than the bench I could plump a hard line straight out of the side of the box, along the top of the bench with a 90 down through the access hole. It seems to me like this would provide less resistance and smoother airflow than that flexible stuff. I'd probably bring some flexy stuff in case I had to move or change something.

As for the box, would the box being under a small vacuum encourage the lid to form a good seal so long as there was some sort of o-ring or foam there to allow a good seal all the way around?

[Canoe]

Trance is talking about a chevy suburban.

Sorry.
Missed we'd changed applications.

What about building a new "rear wall" that fitted across the whole back door. Have a hole for a uni-cooler on one side and on the other side a door and an exhaust vent high to the side. Like some have done for the box trucks? That way you can use it all the time.

A little harder to fit as there's no roll door coming down from the top, but perhaps those large pool noodles would make fitting the sides and top easier?
No changes to the suburban and you can run your cooler anytime and be full sealed.

[Canoe]

Anything rigid, sealable to the intake duct, sealable to the bucket output duct and with a rigid sealable lid. Note that the box will be under vacuum pressure from the swamp-cooler fan so everything MUST be rigid enough to resist that pressure and sealed. As much space as possible around the bucket for the air to flow easily to all the bucket holes; you want to use all of the holes/filter for air flow (one reason why a uni-cooler variation would be easier).

> If I found a box that sat 6"-8" higher than the bench I could plump a hard line straight out of the side of the box, along the top of the bench with a 90 down through the access hole. It seems to me like this would provide less resistance and smoother airflow than that flexible stuff. I'd probably bring some flexy stuff in case I had to move or change something.

Should be fine. Would recommend the same regarding size. If the output is 6", make the input 8". Means the input shouldn't be impeding the air flow required.

Note that hard 90's have more resistance than a larger radius curve with flex (flex gives a good boundary layer next to the wall for low resistance air flow with no joint seams along its length to disrupt - but not that stupid big-fold side wall stuff), but the difference here will be minimal, so go ahead with the hard fittings (you can't crush them either). With the rigid, you watch out for inside seams, but for such a short run if you're going 2" over and you've got at most two seams, no worry.

Watch out for clearance with the table on your cool output.

Watch for enough space inside the box for air to get around the swamp-cooler to all of its intake holes.

>As for the box, would the box being under a small vacuum encourage the lid to form a good seal so long as there was some sort of o-ring or foam there to allow a good seal all the way around?

Maybe.
I'd be looking at some silicone and sealing it up for the duration. You've also got to seal where the swamp cooler duct comes out through the box. Again silicone. For fitting a re-fill tube/hose, you can use hard fittings like I showed in the auto-refill scheme, seal with silicone or use rubber grommets.

Aluminum foil tape (2.7mil, 3", plumbing/hvac supply store, not box stores) may also be your friend; as it's vacuum we're dealing with and not positive pressure, the tape may do the whole job itself. It will stick to the plumbing fixtures you use. Easy to test if it sticks to the box you use. A lot easier and no smell, with easy repair in the field.
If you want an access hatch to be able to reach inside (so you don't have to remove the whole top/lid and disturb the seal between lid & cooler output), cut a hand+ sized hole and seal it with the foil tape. If that hole is rectangular, then you can take the piece you cut out and rotate it 90 degrees and place it across the hole and tape in place to give the sealing tape some support. You could even hinge it so you don't lose it.

Yeah. I'd be looking at that aluminum foil tape really hard.

[trance728]

Is there any benefit to having the water and pump inside the cooler, besides making it a single piece unit? I was thinking about pumping the water onto the cooler pads from a separate reservoir with a return drainage tube from the cooler, so I am wondering if there would be a downside to that other than the extra construction and pieces.

[Canoe]

Fewer points where it can fail.
This is bigger than it sounds.

[Canoe]

What about building a new "rear wall" that fitted across the whole back door. Have a hole for a uni-cooler on one side and on the other side a door and an exhaust vent high to the side. Like some have done for the box trucks? That way you can use it all the time.

http://eplaya.burningman.org/viewtopic. ... 70#p914007

Only instead of built-in to the wall/door, your swamp-cooler would be an uni-cooler style sitting outside on the gate against this wall/door. You can lift it off and set it on the ground/table for use like FIGJAM suggested.

[FIGJAM]

Is there any benefit to having the water and pump inside the cooler, besides making it a single piece unit? I was thinking about pumping the water onto the cooler pads from a separate reservoir with a return drainage tube from the cooler, so I am wondering if there would be a downside to that other than the extra construction and pieces.

The simpler you keep it the happier you'll be.

We're talkin playa time!

How much of it do you want to spend foolin with the coolin?

I tried to make the designs as simple and fool proof as I could for that very reason.

[FIGJAM]

If the forcast holds as predicted, it will only be in the upper 80s for burn week!

[Canoe]

If the forcast holds as predicted, it will only be in the upper 80s for burn week!

And at night?

[FIGJAM]

Mid 50s!

[Canoe]

Thanks!
Note to self: bring good sleeping bag this time (the other blue one); leave skis & skates at home.

[Talynt]

Figjam, I've been following this thread since the day you posted it... I think you might win the ePlaya!

Quick question now, there are 72 freaking pages! I've read the last 20, and I have a slightly unique question.

our camp is renting a very large generator, so I actually will have a 10 amp (ish) 120v AC plug running right to my camp. Thats on my 150 foot 10 gauge extension cord... However I haven't seen many posts that reference how we can change things when we're not limited by power.
For example, I see a lot of these DC computer fans that are rated at ~120 CFM... Is that really putting out more air/pressure/something then a cheap, say, $30 bathroom fan at 100 cfm? Just the size alone, really?

I'm eating into my budget pretty quick, so I'm hoping that going AC will actually SAVE me money on solar powered fountain pumps etc... Got any tips for what I should replace for equal/better performance at the same or lower price point?

thanks! Even a link to the relevant posts would be nice, I can't figure out the proper search term

[Canoe]

For 120 VAC instead of 12 VDC, you've got both a fan and a pump. You could probably source something in 120 VAC, but FIGJAM's done a lot to find, test and prove components that work well. And, if you go 120 VAC, you're now dealing with potentially lethal electricity when wiring up your swamp cooler and its water.

In this post
http://eplaya.burningman.org/viewtopic. ... er#p955267
FIGJAM recommends and links to a 12 VOLT DC POWER SUPPLY PLUG 3 AMP WEARNES WALL WART 3A

12 VOLT DC POWER SUPPLY PLUG 3 AMP WEARNES WALL WART 3A.JPG

He linked to that one for someone asking about a particular fan that draws 1.25A, so if your swamp-cooler was going to use a fan that draws more amps (say an Endless Breeze on high, for 2.3A to 2.9A depending on who is providing the number), you might want a 4 amp wall-wart just to be sure you have room.

The current draw is so low for the recommended components, that a wall wart is sufficient to convert from 120 VAC to 12 VDC. This way you:

• get to use the recommended swamp-cooler components - you know they will do the job properly and reliably on-playa,
• avoid any concerns from 120 VAC power,
• in future, should you go to battery or solar power, you just delete the wall-wart - no need to buy another fan & pump that run on 12 VDC, or rewire your swamp-cooler.

[Talynt]

you're right that 120vac is more dangerous, but what I was referencing was using off the shelf components with minimal wiring (I'm pretty adept at a soldering iron and an arduino, just looking to simplify) to replace the "lack of power work-arounds" that most people have questions regarding.

For example, does a small computer case fan at 130 cfm REALLY put out more airflow (airflow, pressure, power, etc) then a full-on ceiling mounted bathroom fan at, say, 110 cfm? I mean, that just doesn't seem probable... And it'd be SIMPLE to wire up!

And for a pump, wouldn't it make more sense to use a high-flow aquarium pump, or fountain pump, that runs on AC instead of trying to hunt down that out of stock harbor freight solar powered pump that barely works in perfectly direct sunlight etc etc?

I'm all ears, just seems like the parts could be pretty different if you take the power scarcity out of the equation

EDIT: The fans I'm talking about are like this one:
http://www.homedepot.com/p/Air-King-Hig ... fYiqGRgY-M

[FIGJAM]

You are both right!

The designs were made to run off 12 volt DC because that's what most people would have access to.

I tried to find cash and carry for all the parts, but just could'nt and still have something that would work.

If you have unlimited house current it gets real easy.

HF has a lot of 110 AC submersable fountain pumps on their shelfs.

http://www.harborfreight.com/158-gph-mi ... 68396.html

With that power available I would built the box cooler with an off the shelf fan.

I don't see any CFM stats on these but they should be fine.

http://www.walmart.com/search/search-ng ... 4=&veh=sem