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abcdefg1675
03-04-2003, 01:37 AM
One of my many projects are taking and old refridgerator, cutting it up, putting the parts in an old junk computer case, solder then back together, charge it with pure propane (1$/lb at target, VS 11.99$ for 134a at wall-mart :D ).

I will be using this semi-portable refridgerator for things like water-cooling my 500 gallon swimming pool on hot days, cooling my 50 gallon swimming pool that i put fish in (when a swimming pool sits in the full sun on a summer day, things get too hot).

I know how to remove all of the parts from the refridgerator safely( already have that part done) but now i need to get a crecent wrench, let atmospheric pressure into the system (refridgerant has been evacuated already), get my hacksaw, bolt the parts down in the computer case, and solder it all together.

Ive never done any soldering besides repairing electronic things like monitors, tvs and whatnot. My uncle is letting me borrow is propane torch (the type that screws onto the 1-3lb tanks you can hold onto). Im sure it can heat up 1/4" copper pipe hot enough, but i dont know what to use to fuse the piping together.

I wont be using flared fittings, i just cant afford it. I use what i can cut off broken airconditoners. I have some aluminum/tin metal things that you use to tie chain link fence onto the poles, some lead solder ( its too expensive to use up a lb or so on the fridge).

what should i do? is there some guide/tutorial somewhere i can download, open up on my 286 monochrome laptop and read while working?

angryk
03-04-2003, 02:31 AM
What you should do is read through all the threads on this site. After that, Re-read your last post.:cool:

Dan
03-04-2003, 04:39 AM
What you should do is read through all the threads on this site. After that, Re-read your last post.

Or lacking that considerable effort, just solder the copper tubing like you would any copper tubing.

If you are looking at combining copper to aluminum or other dissimilar metals, epoxy is a simple idea.




wont be using flared fittings, i just cant afford it. I use what i can cut off broken airconditoners. I have some aluminum/tin metal things that you use to tie chain link fence onto the poles, some lead solder ( its too expensive to use up a lb or so on the fridge).

Metallurgy does not become you... nor me.:)

I honestly have to ask you, though... what are you attempting and what resources are available to you?

More to the point, can you revise your question?

frank
03-04-2003, 06:21 PM
Don't use the lead solder on fridge piping - it's just not up to the job :eek:

frank

abcdefg1675
04-04-2003, 06:35 AM
im soldering/welding 1/4" copper piping to 1/4" copper piping. I did find a 5$ bill in my room, so that expands my budget from nothing to almost nothing.


I have many pieces of tin wire thats 1/8" diameter. What i am attempting to do is to cut a 1/8hp compressor loose from an old condensor and evaporator, solder it onto an aluminum evaporator from a toyota (this will be the condensor) and many S shaped coils of copper piping for the evaporator.

Then i will have water/antifreeze mix run over the many loops of copper piping to cool things such as a swimming pool, my computers, or a 1000A (RMS) SCR im thinking of buying from ebay.

all i have to do is cut the old lines to the refrigerators evaporator and condensor, put it in the computer case, solder it back together and hook up an evacuation pump. pretty much a simple job.

frank
04-04-2003, 07:39 PM
You just can't make this up can you! :D :D

Andy
04-04-2003, 09:20 PM
Hi Frank,
I have worked on old fridge systems with lead soildered joints, can't say they were great, but they worked alright with R12.
Regards. Andy

Dan
05-04-2003, 03:15 AM
Hi Frank,
I have worked on old fridge systems with lead soildered joints, can't say they were great, but they worked alright with R12.
Regards. Andy

I think for alphabet1675's purposes, plumbing solder will work just fine. But affecting a swimming pool's heat with a domestic fractional hp compressor is something worth calculating.

It will provide a feel for things.

50 gal = 8.7lb/gal=417 lbs
1 btu=amount of heat to raise or lower 1 lb of water 1 deg F.
So we need 417 btu/hr to make a 1 deg F change in the temperature of the water in one hour.

If the water has no other heat influence on it... such as radiant (sun) conductive (glass temperature) or convective (air moving) we should be able to cool the water 1 deg F in one hour with the application of 417 btu/hr.

I would enjoy taking this farther, but I just got home from a week out of town. The next thing I need to look up is how many btu/hr your compressor can accomplish.

I will take an instinctive stab and say it is rated at -15 deg F and can do about 2,000 btu/hr.

The dead end I expect to run into is that we are trying to cool water in full sun. I wonder if there are suggested heat loads for that! 50 gallons can be distributed in so many different ways!

Gut feel? You will not be able to notice any improvement in water temperature in a 50-gallon pool. And that the compressor will fail in short order due to the high suction pressures and superheats it will endure because the evaporator and load imposed upon it is forcing it to operate well out of its design parameters.

Oh boy... good time to stop. I swore to myself many years ago that I would never use the word "parameter."

Oh, and Frank. If I understand you properly, "You just can't make this up."

I am laughing. But the wild geese are much more fun chasing than the tame variety.

:D

frank
05-04-2003, 09:01 PM
Dan

My stomach hurts! :D :D

abcdefg1675
07-04-2003, 01:23 AM
its not a 50 gallon pool, a 500 gallon one. I have several large maple trees in my yard, and where i live it usualy isnt sunny.

It seems theirs something wrong with my compressor. I plug it in, the piston goes up and down a few times and the motor buzzes loudly. I had it running yesterday... It looks like its gummed up with all of the refridgerant oil. Remeber earlier in this post when i wasnt sure if it had ***** in it or not? it had very little, maybe a teaspoon. i unscrewed the service port, oil came shooting out for a second then a slight hiss for maybe 5 seconds after that. I guess running the system for a long time without refridgerant moved all of the oil into the compressor.

I know of a place where i can get a 3/4hp compressor for free. My brother accidentally pinched the line on it and it pissed out the refridgerant.

my 8000btu window airconditioner uses R22. Its a 3/4hp one, works fine. My refridgetaor compressor looks like a 1/4hp. I can also get ahold of two other compressors that might work, one thats 1ft in diameter and 1.5' tall, one thats 2' tall and 8" in diameter. the fat one is 2hp, the tall one is about 1 1/2


so, 500*8.7=4350lbs. i want my water to be about 75, no colder. so, i need to go from 90 down to 75. (90-75)4350=65250 BTU's. 8000/65250=8.15625 hours. Ill have the waterpump controlled so the water flowing through it moves slowly, so the evaporator will be within "operating parameters"... Dont forget the condensor is from a cooling system that moves tens of thousands of BTU's.

Not calcuating in the heat losses through my water pump an lines. The 115v water pump gets hot, very very hot. it will also be watercooled, it pumps out 18W of heat.


Maybe i should pull the 6 cylender compressor off my car, and hook it to a 15hp briggs and stratton engine, that would give me at least 30000btu's if i do it right... it would still take 2 hours to cool the pool.

Stuart
08-08-2003, 10:46 PM
I feel this project is doomed from the start!!;)

Abe
08-08-2003, 11:38 PM
stuart,

Me thinks this guy is taking the piss...........

Karl Hofmann
09-08-2003, 09:49 AM
But he does have the basis for a very entertaining sitcom!

FreezerGeezer
10-08-2003, 08:55 PM
ROFL!!!!!!