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weinerbug Mon Jun 02, 2008 7:02 am

Here are some photos of the Ice Cooled AC unit for the beetle sedan. It is based loosely on the original optional units from the early 60's.



I made mine a little more trim but went with the curves from the dash contours and the chrome trim and ivory knob to match other dash components.
It is ice cooled. Inside the under dash insulated fiberglass unit is a copper chill coil and a three speed fan. It can work with 6 volt or 12v.



Under the bonnet is an insulated PVC unit that keeps the ice. There is a washer pump connected to circulate the ice water through the coil. Inside the 4" PVC is a stainless screen to keep the ice from clogging the inlet.
The washer pump only comes on when the fan switch is turned to low medium or high.
Drops 80 degree inside temp to about 50 degrees at the bezels. Haven't tested in real life yet, but so far so good. Runs for about 4 hours with full 4 pints of ice blocks.

67 Florida Deluxe Mon Jun 02, 2008 7:05 am

Wow :shock: ! Very nice workmanship :D . I would put ice in my swamp cooler to make it cooler. Yours is a lot more streamlined than a bulky swamp cooler hanging on the door :? (and it looks good, too :wink: )


warduke75 Mon Jun 02, 2008 9:26 am

Did you make or buy? How or where?
and hey '67 Florida Deluxe ', if you wanna sell yer swamp cooler, let me know! Keep getting outbid on ebay!

67 Florida Deluxe Mon Jun 02, 2008 9:31 am

warduke75 wrote: Did you make or buy? How or where?
and hey '67 Florida Deluxe ', if you wanna sell yer swamp cooler, let me know! Keep getting outbid on ebay!

Sorry, your luck just got worse. As I was perusing the classifieds recently, I saw a WTB for a very good condition swamp cooler. Since I sold my '56, the swamp cooler was just collecting dust, so I sold it to him - shipped it out two days ago.

I might suggest you put a "WTB" (want to buy) ad in the classifieds. They work :wink: !

weinerbug Mon Jun 02, 2008 9:46 am

I made it of course. By now you guys should be figuring out what an engineering geek I am. Of course you can buy a nice one from Gilmore Enterprises, but what's fun about that?

You really want to know how I made it? How much time do you have?

I started with a foam mold, cut and sanded to shape, sealed with plaster and sanded again, sealed with a mold release and covered with two layers of fiberglass and sanded again, primed and painted.
The chill coil is just 1/4" copper spiral coiled 6.5" diameter twice. Couldn't find a reasonably priced oil cooler or heater core the right size.
The fan is a pet cage fan cut a bit.
The switch is from radio shack with some resistors and made to thread on the VW knob.
The under bonnet unit is made from 4" pvc, end cap, straight section 14" long, a 90 degree elbow with a screw on cleanout. The stainless screen is jammed between the straight and end cap. This component could be made smaller or bigger.
The fittings are 1/4" NPT to barb fittings.
The washer pump from auto supply.
The bezels are from Summit Racing Supply.

To refill the ice, you drain the ice melt water and add like four or five frozen plastic cups of water. The plastic cups are tapered, party cups.

Total cost was - $136
PVC $20
SS Screen $4
Fittings & hose $10
Fan $11
Bezels $45
Switch and resistors $5
Knob $4
Fiberglass $21
Washer pump $16

67 Florida Deluxe Mon Jun 02, 2008 9:52 am

Not dogging your work, but my only concern would be the life span of the washer pump. They are not engineered to run constantly, so I would wonder how long they would run before they failed. Did you consider any other types of electric pumps that may be heavier duty (like a small fuel pump, perhaps)?

weinerbug Mon Jun 02, 2008 11:26 am

Well, you are right. That washer pump may not be good. It will probably run a little longer on 6 volts. I had it laying around. I have tried fuel pumps with water and they don't do well. The fuel lubricates them. Water quickly rusts them shut tight.
I just wanted small. What else? Hmmm...
I had thought originally to use a bilge pump inside the ice reservoir. That may work. Hard to service the way I put things together. Maybe the end could screw on too and then you could get at the pump.
Thanks for the dogging, Howoooo!

onebad65 Mon Jun 02, 2008 12:24 pm

your project looks bitchin, let us know how it works on a hot day, what would happen if you put dry ice in it? im thinking about making a similar unit but i want to be shure it will work good enough to spend the time on it.

weinerbug Mon Jun 02, 2008 12:46 pm

Well, dry ice? Water can't get colder than 32 F without freezing, so dry ice wouldn't drop the temp in the circulating water, but might freeze up the reservoir solid. Add salt and you can get colder, but salt is corrosive to lots of parts. But, you are thinking and that's a good thing.
Dry ice gives off a lot of CO2 when it evaporates, so it would have to go somewhere.
This unit is designed to get me to work and back with a degree of comfort. It blows out really cool air and feels good. Oh, the fan is no louder than a normal car's AC unit.
Also, there is a minimum of hacking a nice old car in case I want it out.
Luckily Michigan is only hot for three months.
I'll give a good report in a couple of days.

hemifalcon Mon Jun 02, 2008 1:42 pm

The only other idea I could think of for a 'water' pump would be those small pumps you get at gardening outlets for fountains. they can run for hours, and they run on 120, but I'm sure you'll have no problem if you just run a small inverter in your car to operate that thing. That's a very cool setup though! Just like your ragtop creation, great work!

onebad65 Mon Jun 02, 2008 2:13 pm

i was thinking about using the dry ice to make the regular ice last longer, maybe insulate the dry ice alittle to keep the water from freezing solid and then vent the co2 to a location out side the car,

metalchomper Tue Jun 03, 2008 9:01 am

I would suggest one of these: http://www.hargravesfluidics.com/liquid_pumps.php

These are good pumps. I designed the initial series of pumps before leaving the company to design bigger pumps. Someone tried to make a production motorcycle seat cooler with one these, butt the market wasn't there. (pun intended) :D

weinerbug Mon Jun 09, 2008 10:52 am

Well. I went to the VW show in Ypsilanti MI yesterday. Great show and wonderful people. The weather had been wet and rainy until 7:30am, cleared up and was sunny for the show. Later at about 6pm it poured and blew and power went out.
Anyway, I filled the unit with ice at 8am. The ride to the show took 30 minutes. The unit on low is pretty meager so that could probably be elliminated. I just set it at high the whole way.
The outside temp was 79, and with windows closed the inside temp dropped to 73. It was sunny. The feeling to the skin was pleasant. Anyplace the blower hits you it feels cold. A very pleasant ride with windows closed. Quiet too.
On the way home at 3pm it was about 90 and really muggy. There was still some ice left. For about ten minutes the cooler was still putting out cool air. The inside temp of the car closed up only got down to 85. Again where the blower was hitting me it felt like a cool forest at the state park.
Had I fully loaded the ice before the afternoon trip it might have been a better test.
Ten minutes into the trip home I had to open the windows but the blower still felt good.
I'll do a more scientific test soon.

jmsmilin Mon Jun 09, 2008 8:07 pm

very cool

VOLKSWAGNUT Tue Mar 16, 2010 12:29 pm

weinerbug wrote: Total cost was - $136



Labor is always free when its your own.

Very nice work, you should start a line of "Chilled Air Cooled Coolers" for VW's. Great idea for road trips, I dont see the practicality for every day driver cars.

Here in the humid/hot south that ice would last about 60 minutes in June. But I like your idea.

Where do you drain the warm water when your done?

On a side note, some cars have an electric aux coolant pump that is designed to pump coolant to remote heater cores. Ive also seen these on motor homes. Small, quiet, and designed for water/coolant.

andy_t Wed Mar 17, 2010 9:53 am

Have you looked at these pumps. They are 12v water pumps for RV sinks.

http://www.adventurerv.net/shurflo-nautilus-single-station-water-pump-gpm-p-1713.html

atye Wed Mar 17, 2010 10:18 am

For those of us in the South, what about a larger box for the ice... :idea:

Say, a Coleman cooler hidden behind the backseat? I know that there are coolers that advertise that they can hold ice frozen for a couple of days. The pump and everything could be mounted inside, the coils could be a good bit larger, etc.

Hmmmmm...

ecvwfan Wed Mar 17, 2010 8:16 pm

Any word on this? Was it a success?

SKIN Thu Mar 18, 2010 7:02 pm

I am digging this man.

seanboy69 Tue Apr 06, 2010 7:35 am

Any more info on this??? Somebody should build these for us engineering challenged 8)



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