Posted by Brian W. on July 21, 1998 at 14:48:20:
In Reply to: Re: Cold Air Study posted by Steve P on July 21, 1998 at 03:38:42:
The smallest refrigeration unit currently available for this job would be a small dehumidifier. These usually have 1/4 HP compressors (the same as a frost free fridge) and a large volume fan.
These are a balanced system whereby the room air is brought in over the cold coils (to remove the moisture from the room air) and then the air is reheated by the warm coils to the rear as it is returned to the room out the back of the machine.
The cold air might be short cutted through an added air scoop through the top of the unit. The ones i describe stand on the floor and are about knee high. The sheet metal jacket will remove by taking out the screws that hold it in place and a person can see the complete unit in operation. Perhaps a baffle would be necessary in front of the warm coils to encourage the cold air to exit the top of the machine, where a person had cut a new exit hole. A short piece of dryer venting tubing should perform as a delivery system..as such, the new, added hole should be 4" diameter.
This is theory..if anyone experiments with this design, please be careful. Do not damage any refrigerant lines (all the metal tubes carry refrigerant) and there will be live electrical connection exposed if the jacket is off and the unit is plugged in.
An alternate plan might be to remove the fan blade,(approximately 8 inches in diameter, plastic) and go to an appliance parts place and buy one with an opposite pitch..this would essentially reverse the airflow bringing room air into the warm end of the unit and allow cool air to exit the front.. although the temperature of the exit air may not be cool enough by this method.
The cool coils of the dehumidifier will exhibit frost, proving that the temperature would be 32 degrees or colder.. it should work.
Things are too busy around here these days for me to experiment right now so if anyone tries this please let us know. I should have time in the fall.
All the best for painfree days a'head,
Brian W.
PS.. These units run on 110 V and draw about 5 amps. I don't know of a portable unit for 12 V. other than existing car air conditioning. (which is very heavy horsepower compared to domestic refrigeration)