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View Full Version : An idea for a chiller...


PoX Freak
11-11-06, 07:10 PM
OK, I've got this oversized Pepsi fridge at work, and it just screams "chiller setup".
Specs are as follows...
5.6 Sq Ft, 120V, 3A, refrigerant r134a, pressures: high side 390Lb, low side 150Lb.
It has an evaporator behind a "wind screen", basically a sheet metal cover which is fan-forced from above with a Papst 120x38mm fan, and a thermostat coupled directly to the evap.
The instruction sheet says "set thermostat to 5 (range of off to 9) for liquid temperature of 36-38 degrees farenheit. This is an average range, and can be adjusted."

The evap is approximately 5x8x2-1/2", and mounts to the back wall. The entire unit can be extracted from the fridge through the bottom without disassembly.

Here's the "problem"...
It sits there because the thermostat is apparently bad. Set it to "1", and the fridge hits 20 degrees F, set it to 9, and the thermometer reads -18 degrees F, freezing anything inside.
The thermocouple is in direct contact with the evap, and it still does this. Pull the thermocouple out and it runs continuously, unless it's set on 1, which it will shut off at about -20 degrees F.

Bring it home, change the thermostat and run it as a chiller, or leave it there?
Pepsi shows no record of the property number, nor do they have an aquisition number, and they don't intend on picking up the unit.
still, it sits in my office just begging to become a chiller.
Question is, how efficient might this be? Will it be enough for my rig in the post? or will I end up with more junk for the wife to yell about?:rolleyes:

greenmaji
11-11-06, 09:22 PM
Can you find a make and model number off the compressor?

PoX Freak
11-19-06, 05:47 AM
This might take me a little while, since the compressor is buried inside the base under 2 different covers, one with a 6"fan.
But I do have the unit home and can tell you this;
It will form ice on the evap, which is half immersed in water, about 6-8 minutes after start up with room temp water (21ºC), and will continue to ice up until the entire 1 1/2 gallon container is almost full of ice.

BTW, My reply was delayed because of this unit. As i was pulling the evap from the sheet metal duct inside, my middle finger skipped along a sharp edge and i cut a tendon on the back of my middle finger (i looked wierd with my finger out at everyone all this past week). This put me off the unit for this past week, but I plan on getting something done with it today.
Pics will follow...

4od
11-25-06, 03:15 PM
how many tons of refridgerating power?

XeonStrikeForce
11-28-06, 08:45 PM
Thoughs units usualy have a 6,000BTU/pH (1/2Ton) Compressor in them.

Pf.Farnsworth
11-29-06, 04:07 PM
how many tons of refridgerating power?

Better off measuring in watts, makes math easier, good old energy over time :)