Are computer fans really a good option?

[noseoil]

I've looked at some threads about using computer fans for ventilation. There are several schools of thought about them, noise, speed, airflow, etc.

1 - They use less energy, the 120mm fan only draws about 0.5 amp
2 - They are very quiet compared to a Fantastic fan
3 - They flow less air than a regular vent with the larger 14" fan
4 - They would cost less than a $140 regular fan ($40 for a vent & $30 for two fans = $70)

Here's my question to folks who have used them, or a more conventional type of fan, is this a good option for running ventilation on a teardrop? I don't mind paying the $140 for a "store bought" type, but after reading about the noise, people trying to slow them down due to airflow & other things, is the computer fan installation really a good alternative? Are they designed to run in a "flat" position and last long enough, or do they have to run in a vertical position?

We will have AC for hot weather, but I'm not camping here in Tucson in the summer (have to be nuts to do that & I'm not quite there yet). At higher altitudes and farther north, will this type of setup work well enough? I'm thinking for the same $140 I can have a metal side vent, two computer fans, a metal roof vent (durability) and everything I need to make it work.

http://www.newegg.com/Product/Product.a ... fgod3nQAFQ

Any and all input is welcome. Thanks, tim

[pohukai]

For me, yes. But when I built TD, I wasn't sure either. I framed and wired for the fantastic fan, but use computer fans knowing if it wasn't a good option, I could still go out and pick one up. For me, this route would have been a lot less painful than going the other way (slowing down the fan, making it quieter, etc)

[SLUG36]

I have a couple of computer fans hooked up to force air through the coils in my 2 way fridge. the ones I have are quite noisy. but they were scavenged from old PC's. on the other hand. they do seem to move a ton of air relative to their size.

the ones in the link posted are 25db. that would lead me to think they might be quite noisy too.

[tony.latham]

My first 'drop had a computer fan that was noisy. It didn't pull enough air. I added a second one and it too didn't move enough air.

As pointed out in another thread, all computer fans are not created equal –I get that.

I put a low-profile reversible Fantastic Fan in my new tear. I really like it. I don't consider it noisy. When it's really hot, I like the fan blowing down on us. I forget the exact amp draw, but on the low setting –which is what I normally run it on– draws something like 1.5 amps on my meter. For an afternoon nap on a hot day, it's good to blow the heat out on high and then lower it down to the lowest setting.


It's also nice to just crack it open for ventilation at night when the fan isn't needed.

Tony

[citylights]

Fantastic fan will blow like a fan. Blow on you and keep you cool. It will also vent in a hurry.

Computer fans will provide ventilation, air changes in the teardrop, but they will not blow on you enough to keep cool like a fan. If you just want to change outside cool air for inside, they are fine. If you want them to blow on you to keep cool, no go.

I have a fantastic vent and I like it.

If I was going to use computer fans, I would install a regular roof vent, then at least two computer fans (maybe two sets of two) set in the teardrop sidewall. In the sidewall, they will set just like in the computer, and they will be easy to change and not require a custom bracket for mounting together at the vent. The fans would draw in outside air at the wall to let it vent out the top. There are a variety of wall vent coverings at the big box stores that would work to cover the vent hole from the outside.

[mallymal]

For a redneck cheapo option, I wonder if something like this could be cannibalised?

http://www.amazon.co.uk/HDE-Ultra-Power ... wered+fans

Cheers

[pmowers]

I have one of these, that runs on 6 D cells for a very long time, or on 12 VDC. I seems really quiet, moves a lot of air and has a hi/low switch. I just mounted below my vent and let 'er go. Since it will run for hours on some D cells, I do not think that it has much in the way of current draw.

http://www.amazon.com/O2COOL-NEW-Battery-Operated-Adapter/dp/B00ATSHMIQ/ref=sr_1_2/183-8674148-2635133?ie=UTF8&qid=1411331892&sr=8-2&keywords=o2-cool+fan

I got mine at Walmart, in the camping section, labeled as an Ozark brand.

[Shadow Catcher]

We have two Antec 80mm three speed case fans with a switch that allows one or both to be used. Ours is a large tear and seldom do we use the fans on more than middle speed here you see versions one and two.

[working on it]

Here's an excerpt from the thread "Fantastic Fan Overload!"

So in theory a few case fans would be sufficient. I couldn't find your build thread to answer the next question of how did you run them for best ventilation vs waterproofing and how many amps do they draw? Thinking if I can trim the amps I can get a cheaper battery.

I have tested/used two high static pressure Corsair SP-120 case fans (bought to force-flow air thru close-set, weatherproof vent covers - normally very restrictive) which flow 67.2 cfm each (134.4 cfm total) in my 81 cubic foot cabin (unfilled, available airspace, max), so I get the air exchanged every 36 seconds while just drawing .18 amphours each at 12vdc. I tested them one hot night, and only resorted to adding my .275 amphour draw (x 1.2, since run off the battery thru an inverter), when I wanted it cooler for sleep. As I reported here, from an earlier post:

At my first trailer gathering, as I showed some of them my trailer's features, someone remarked that "if your trailer is as airtight as you say, then you'd better leave the butterfly vents open". Another commented that the placement of the vents being high up on the walls, would not vent out any accumulating CO2 (heavier than air?). That worried me a bit. So during my first night out, I opened each vent halfway, and ran the A/C. It froze me down to 65 degrees before I figured the right setting to maintain 72 degrees (still used a comforter). Later that night, I awoke as the electrical had come unplugged (kids in camp next door?), and I still was under the covers and hot. So, instead of getting up and restoring 110vac power, I decided to test the 12vdc case fans as ventilators, with no main fan, nor A/C running. I turned them on, opened the butterfly vents all the way, and settled back to see. After 3-4 hours (as I listened to my MP3 player),I was still breathing, though the trailer cabin was now at 86 degrees and humidity 75%. Livable, but not comfortable. The test was a success, so I turned on my inverter to run my 110vac fan off the battery (still didn't get out to fix the unplugged park power line), and I went back to sleep. The next night, I didn't even need the A/C anyway, and slept soundly , assured that the computer case fans or the bigger 110vac-powered fan moved enough CO2 out the vents to keep me alive.

I didn't even bother opening the two side windows, as the fan (on low speed) actually made it cool enough that I still covered up with the comforter. It didn't reduce the humidity, but felt good enough for me. Combined, the two different types of fans performed excellently, and even if it had been pouring rain or (blowing it sideways), no possibility of leaks, as no open windows or unshielded (side) vents were in play. Total amperage draw was only .69 amps per hour, and I could've done without the case fans once the bigger fan was utilized.

I installed my case fans blowing out the front upper vents, as a 12vdc ventilation source, just in case all 120vac sources failed. And since they draw so few amps, they're good for an entire weekend, without a recharge. But they're only the last resort...I've not even turned them on in the last year.

corsair case fan 120mm.jpg (76.65 KiB) Viewed 1487 times

[Vedette]

As I did not want a rooftop fan in Miss Piggy I installed a four speed nose fan that moves a ton of air if we want to use it or need too???
But, we have two computer fans that we run every night (last night being our 100th) to eliminate condensation build up.
They work GREAT!
And they are quiet too!
They don't run our battery down when we are off of the grid.
And they were cheap to free!
Good Roads
Brian & Sandi

[DMcCam]

One thing about the Fantastic Fans for consideration, they are known for reliability and made specifically for their purpose. If you are ever to sell your trailer in the future, a potential buyer will accept it as a 'real' trailer part. We installed ours because of the overwhelming positive feedback by users. After camping with it for two years I am now a full convert. They are well worth the money and work as advertised maybe a little too good really.

As to the computer fans, why not? Each home made trailer is a prototype. If you are not 100% sure the computer fans will do the trick, add the blocking with wiring so you can add something like a Fantastic Vent in the future.

All the Best,

Dave

[noseoil]

Dave, curious about the noise issue. Have you been in a situation where you wished there wasn't so much noise with the fan running? Also, speed, is low speed low enough for your build or do you wish these was something slower at times? Thanks, tim

[GuitarPhotog]

Dave, curious about the noise issue. Have you been in a situation where you wished there wasn't so much noise with the fan running? Also, speed, is low speed low enough for your build or do you wish these was something slower at times? Thanks, tim

There's a whole thread here on how to slow down a Fantastic fan. Apparently the noise can be an issue for some people. I use a computer fan to keep the air circulating in my teardrop. It is a 3-speed model and at the middle speed is very quiet but still moves enough air that it doesn't get stuffy inside.

<Chas>

[webpager]

I haven't built my first camper yet. But I have a lot of computer experience. There are a lot of fans out there and they range widely in price. I have some on my current computer that are extremely quiet. But let's not forget that these fans, while cooling down what can be high temperatures, are still used on a 1 to 2 ft.³ box. You will need multiple fans. But another good thing about most of the newer computer fans is that they can be controlled for speed. They are reversible. And they are inexpensive.

I know a lot of campers and other shelters have vents on the roof to allow heat to escape. They also need vents near the bottom to allow cool air to enter.

[DMcCam]

Dave, curious about the noise issue. Have you been in a situation where you wished there wasn't so much noise with the fan running? Also, speed, is low speed low enough for your build or do you wish these was something slower at times? Thanks, tim

Hi Tim, We mostly run it on low and it's about the same noise level as an older refrigerator compressor running. We can easily sleep with it on even at the higher levels. At those settings it moves a lot of air and might be hard for folks to sleep through (as in a good breeze). It would be nice to make it run about half as much at times. I'll likely end up doing the slow conversion at some point. As others have said, the noise level is sort of a personal thing though.

All the Best,

Dave