an idea for A/C

[91CavGT]

I experimented with this idea today.

I took a cooler I had and put two 10 pound bags of ice in this cooler. I then put a wide window fan on the top of the cooler with the top of the cooler open. The fan was setup so that it blew air out of the cooler. I closed the lid partially on top of the fan which in turn directed air from the fan towards the front of the car. This was sitting in the back of the luggage area in my station wagon.

My 2 sons and I then drove to my sister in laws house an hour away. The windows were up the entire time. Currently there is no window tint on the car so it usually heats up pretty quick in the Texas heat. The outside air tempurature was in the mid 80's with dew points in the low 70's. Needless to say it was VERY muggy. After an hour drive, there was still ice left, but the tempurature in the car had not decreased. It felt to be in the low 80's, about the same as the outside air temp.

I believe if I had the fan blowing air down into the cooler instead of sucking air out of the cooler then it would cool the air off better. I'll try this next week on Tuesday or Wednesday. I'll also grab my digital portable thermostat to get an accurate temp reading. Temps are supposed to be in the 90's next week too so it should be a good test.

[GasSavers_JoeBob]

My mother told me a story about a vacation she and her mother took in 1937. They drove their '29 Oldsmobile from Lincoln NE to Santa Monica, CA. For driving across the desert, they put some dry ice (presumably in some sort of container) by the outlet for the vent in the car. The incoming air was cooled by the dry ice, making the drive across the desert more comfortable in that pre-A/C era.

91CavGT, your idea, since you have to reload it with ice on a regular basis, seems awfully labor-intensive and ultimately more expensive compared to the benefits derived. But that's just my opinion.

A station wagon is a large area to cool. I'm not surprised that the ice didn't do much. In the '70s, I had a couple different cars with comparable A/C systems...a '66 Malibu sedan which got nearly cold enough to hang meat. Then I had a '65 Plymouth wagon with an A/C at least as big if not bigger...but more volume and large windows on the back. A/C could barely keep the car comfortable. I often wondered about those Plymouth Barracudas with the BIG back windows...

My thought (if I ever get around to it) would be to put together some sort of absorption-cycle refrigerant system, similar to the natural gas Servel-type refrigerators. Using the exhaust heat as a heat source.

[91CavGT]

Interesting read. My commute in the afternoons is about 45 minutes long and sometimes my wife will be with me. I've got a free and endless supply of ie at work so that's not costing me anything.

Do you have any more info on the absorbtion-cycle refrigerant system? That sounds like something I'd like to read up on.

[GasSavers_Erik]

Just a word of caution for anyone wanting to use dry ice to cool their car- do not just put a couple of huge chests of dry ice in your back seat and roll the windows up. It will sublimate into carbon dioxide gas which could suffocate you if you had your vents in the recirculate position. I'm sure there was enough fresh air coming in to that 29 Olds to dilute the carbon dioxide from teh dry ice.

[GasSavers_JoeBob]

Originally Posted by Erik

Just a word of caution for anyone wanting to use dry ice to cool their car- do not just put a couple of huge chests of dry ice in your back seat and roll the windows up. It will sublimate into carbon dioxide gas which could suffocate you if you had your vents in the recirculate position. I'm sure there was enough fresh air coming in to that 29 Olds to dilute the carbon dioxide from teh dry ice.

Erik

Good point. If memory serves, the '29 Olds pre-dated rubber door weatherstrips by about 8 or 9 years. They probably also left a window either cracked or all the way open. I can't verify the precise operation...my mother is no longer alive to ask, and she probably didn't remember all the technical details when she told me the story some 40+ years after the fact...she was 15 at the time and more interested in the fact that Wyoming didn't require a driver's license then and the minimum age to drive was 14, so she could drive across that state herself. She was also looking forward to a summer at the beach...probably thinking about all the guys out there...

91CavGT

There is a good description of the absorption cycle (and yes, it is spelled absorption, not absorbtion) here...http://www.gasrefrigerators.com/howitworks.htm

[StorminMatt]

Originally Posted by 91CavGT

Do you have any more info on the absorbtion-cycle refrigerant system? That sounds like something I'd like to read up on.

In theory, something like the absorbtion cycle would be a GREAT idea. But there is one little problem with it: it requires the use of a cooling tower. This makes it rather unsuited for anything but stationary applications.