Have any of you ever seen this? I wouldn't expect it to keep the car at 68 degrees all day in Atlanta summer. However does it do a decent enough job to make a car without ac parts tolerable for a few hours?
Have any of you ever seen this? I wouldn't expect it to keep the car at 68 degrees all day in Atlanta summer. However does it do a decent enough job to make a car without ac parts tolerable for a few hours?
My 8th grade understanding* of thermodynamics tells me that it's physically impossible for this to work well in real heat.
* I studied graduate level thermodynamics but barely passed and currently understand it at an 8th grade level. Maybe.
It's a cooler filled with ice with a fan. Seems bulky and sloshy, but could work. I am going to go slightly more compact and just wear a coolshirt.
It's a cooler with a fan on it. Fill it with ice and it'll blow cold air until the ice is melted, then it'll start blowing warmer and warmer air until the water hits ambient temp. Same concept as most cool suits basically.
Yep, similar concept to a cool suit. However that's with a shirt pressed on my skin in a race car with no windows. Wonder how long it will last blowing the air into a small cabin with the windows closed.
In reply to SKJSS (formerly Klayfish) :
Thing with swamp coolers is they're less effective in humid conditions and need moving *dry* air to be more effective. Otherwise as the air gets saturated with humidity... they get less and less effective. The other thing is as many have found out through the years adding ice to swamp coolers doesn't make a big difference. Most would say it's negligible, at best. Nature of evaporative coolers.
That's not a swamp/evaporative cooler. It's not running off evaporation, it's a heat exchanger with warm air and cold water. It's an air/water intercooler, actually.
In reply to Keith Tanner :
That thing actually has a legit heat exchanger and pump setup in the lid? All I see is the one picture on that website page and a vague description that made me assume it operates like an evaporative cooler. Truthfully I didn't click around to every page of their website, but you shouldn't have to, in order to find the pertinent info, in my opinion.
The other cooler "Ac" systems I have seen are like portocools. They have a wicking medium and a pump to saturate such with the fan blowing across it. Guys with aircraft have been doing DIY versions for years.
Edit... and thinking about it. I *vaguely* seem to remember seeing one with a heat exchanger core designed for planes in Sportys maybe 10-15 years ago. Late 2000's maybe. It was expensive too. Like a thousand bucks or so. Seem to remember it may have had a bilge pump and dump hose setup built into it as well, to make removing it easier.
There's a video on the page, "watch before you buy". You don't need to see all of it, but it does mention the heat exchanger and he pops the lid to show the inside. Also, "not a swamp cooler" is mentioned a bunch of times :)
Really, it doesn't need to be much. Run ice-cold water through a little water-air heat exchanger with relatively slow moving air and you'll get noticeable heat transfer. All the work is being done by the phase change of the ice turning to liquid as opposed to the phase change of liquid to gas. And freezing that ice is a job outsourced to your ice maker, the ice is just storing the work of making the cold (removing the heat) for you :)
I could probably do a DIY version with what I have sitting around the shop. Might not last as long as an evaporative cooler but it'll work in high humidity and I suspect the output air is cooler.
In reply to Keith Tanner :
Gotcha. Didn't click the video link, I'll have to flip thru it quick when I have a chance for curiosity sake.
As far as it working better than an evaporative cooler, wouldn't be hard to. Evaporative coolers work on a quite simple concept and adding ice to them and bringing the temperature of the fluid down can actually impede their cooling effect. There is a LOT to how effective they are as far as ambient temp, airflow, humidity level, etc but the super short of it is at say 90 degrees and 5% humidity (numbers are out of thin air, but you can easily find the charts) you'd be able to drop the ambient temp by roughly 20 degrees. However at 90 degrees and 50% humidity you'd only be able to drop it by roughly 10 degrees. And at 70 percent humidity you'd be lucky to get say a 5 degree drop. They excel in dry hot air. Everywhere else, they suck.
These seem like they would be decently effective for a short period of time, however extremely limited by the BTU's they can throw off. A small auto unit typically is in the 6-10k BTU'S for a typical under dash with a moderately sized condenser. Some of the big boy setups we throw under the dash with modified cowls to fit large evaporators and the also required huge compressors and large condensers up front are in the 15-20K range - for the 4 door wagons and such, and even then we tend to do a rear mount as well. This may seem like I'm rambling... but keep with me for a second here.
Going at a 100% (not at all possible but easier on the math side) efficiency rate for an ice / water heat exchanger setup the max you will see per pound of ice is 144BTU. That means with say 30lbs of ice stuffed in a large cooler at a 100% rate you'll see 4320 BTU'S. Now, with a setup like that honestly they're probably more like a 2800-3200ish BTU setup.
All that out-of the way, it wouldn't surprise me if you could run one on full blast for an hour or two in a 90 degree cabin and bring the temp down by 10-15 degrees. Past that, you'd probably be running out of ice quick. So, wouldn't surprise me if it would work to keep you cool, but a cool shirt would be more effective for a variety of reasons.
Or.. what I would do if it's a matter of not wanting to figure out the accessory drive is start to look towards OE electric car parts in junkyards as some have electric compressors. Obviously still have to figure out the condenser and evaporator mounting, but don't have to worry about redoing your accessory drive that way. With a good strong alternator you should be good to go. I want to say the smaller ones out there only pull something like 40-50 amps at full tilt. Larger ones obviously have a much higher demand, but it all depends on what you're doing. Trying to take the edge off... or set them up like we do. Which obviously has a lot higher demands on everything to make it 60 degrees when it's 100 and humid out there. Just another option to think about. Anyway, my money is on you'll start to see more and more folks go the electric way as the years progress. Especially in hard to package street rod and hot rod E36 M3. And stuff like retrofits into classic smaller sports cars, electric conversions, etc.
In reply to GaryC83 :
Thanks for the all of that info! Unfortunately, I'm very limited by lack of mechanical skill. Whatever I do needs to be plug-and-play or I'd have to pay someone to do it. I love the cool shirt in my race car, but for a street car I think it'd be less practical.
Gotcha. That being said what I would recommend you do is maybe have a look around at some of the homebuilt aircraft websites for a DIY to follow along and see if you think you can follow it in your own. There isn't much to a setup like that. You could easily knock something like that up for a fraction of the cost, even if it's on a slightly smaller scale. If you had say $75 into it, it would be a good way to gauge if it might be worth scaling up for you.
I don't mean to be dismissive of the idea and hope I didn't come off that way, but just to go into things with realistic expectations. It's not going to set the world on fire and drop cabin Temps into the 60s. But id venture a guess a proper system on a typical coupe or sedan body would be more than adequate at taking the edge off, and dropping overall temps by 10 degrees, possibly slightly more, for 2-3 hours, until the ice is melted off. At that point it will still be effective but the point of diminishing returns approaches quickly. Again this all kind of over simplified in a way, but I'm trying to break it down in an easy way.
Obviously anything you can do towards insulating the cabin will help, as will simple things like tinting the windows.
Anyway, like I said, I'd dig around some homebuilt aircraft website. I bet you can find a DIY there. Those guys are notorious for stuff like that, as most aircraft don't need AC up past 5,000 ft anyway and they truly really only come into play on the ground, taxi and climb out, as well as descent, landing and taxi back to hanger or wherever they tie down. You'd be surprised overall how few GA aircraft have an AC system, as its obviously a cost and weight thing, as that junk all needs to be certified, but portable setups like that do not, as they're self contained and independent of the drive and airframe. Just have to take into consideration their weight is all.
Might be worth a dig around to save yourself some cash and see if you think you could knock one up yourself. The other thing to note is a larger unit won't throw out colder air, it'll just allow you to have that same cold air, for longer. Wouldn't be surprised if you could get consistent 45-50 degree air coming out of the thing at full tilt. Have that available for a couple hours with say 40-50lbs of ice. Probably do a fairly decent job of keeping you cool while dropping overall cabin Temps by 10 plus degrees for a few hours on a hot day.
12v AC is a thing, but they are pretty expensive and pretty small. This one is 1500 BTu and $800+. It's only going to cool a very small area.
Rigid HVAC makes some small portable systems in the 2500 btu range. They run about $1400.
If you do some looking on the solar websites, there is a company out there that makes a DC mini-split. IIRC they are 24-48 volts but they are available as well.
I did a few minutes of quick digging. This guys has links to everything he used. Spent about $130 to make his with all new parts and battery driven, said it would be about $100 to make it a 12V DC plug in setup. Very similar to that setup for $300.
https://intothesky.com/homemade-ac/
I'd give the link a look and see if you think that's something you're capable of. I bet you would be.
To give perspective, I am trying to cool a Boxster that has had HVAC guts removed. So the space is small.
How about a coolshirt setup?
I used to use a DIY cooled seat insert in the Abomination. It worked very well and beat having to disconnect hoses every time I got out of the car.
I like Toyman's cool seat concept.
I'm quite familiar with evaporative coolers, as it's what we use on houses here. I'd never consider one for a vehicle, although I've seen some intriguing 50's versions that sit in the window and use the airflow from the moving car to move air over the pads.
EV AC systems may run at high voltage. I think the Tesla ones are 400V. It's amazingly effective but not something that will easily drop into a Boxster. The Vanagon guys are experimenting with some new roof mounted 12V truck reefer units, but they're only barely small enough to be roof mounted above the front seats. I do have a 12v compressor fridge in my van which is basically AC for a very small room :)
I've been looking at these units as an option for my TVR project. I don't have a lot of room for an A/C system, and this would fit fine in the back storage area. See here for more info.
I like that it's battery powered, so you could actually have it running when the car is off. I'm assuming I could find some sort of 12 vdc to 24 vdc power adapter so that the car could charge it when running.
It's not cheap at about $1500, but they've been coming down in price. When I first looked at them 3 or 4 years ago they were over $2000.
Would be really nice for an autocross or track day where you could keep it running and never let the car heat up.
In reply to Keith Tanner :
There's a lot of low voltage (12-24V) systems out there. The high voltage stuff DOES work better, but from a retrofit standpoint a 12v setup is obviously easier.
Heck, there's even a European company making drop in 12V 911 electric AC retrofit kits for early air coolers. I think they're using a Toyota compressor offhand and their own little ECU with what i assume to be PWM type management for it.
Edit: here's that now updated kit. Been a while since I've looked them up. They also have a dual condenser version.
Designed to be a bolt in installation. Pricey, at €3400, but like everything nothing is cheap. Especially when its for a Porsche.
And those window mounts have been around forever. I've restored quite a few. They work "ok" on a good day. That's about it. Marginal at best every other time. They look far cooler than they work. But hey...history and all that jazz. I want to say Thermador was one of the larger manufacturers.
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