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A bit ot : disassembling refrigerators

A

Arpit

Jan 1, 1970
0
Hi, I want to use the pump from an old refrigerator as an air pump.
People are constantly throwing away old refrigerators here, at council
pickup day. Would i just be able to cut the tubing and take the pump
out, or would that result in an eyeful of freon? If its pressurised,
could i csquash the tubing in a vice and then cut it there? Is there
some method which'd allow me to remove the pump on the street, without
carting the fridge back to my house?

thanks in advance, arpit thomas
 
B

Bill

Jan 1, 1970
0
99% of chucked out friges have burnt out compressors, you'll be looking for
a long time to find one that works.
you'd have to incorporate an oil separator, since they require oil to
survive and small amounts do get pumped out.

and its not an issue cutting the pipe, just keep your hands away unless you
want frostbite, they only usually have 300-600gm's of r12 which wont take
long to escape (poor ozone layer).
 
B

Bill

Jan 1, 1970
0
also never cut refrigeration lines with a hacksaw, only a pipe cutter may be
used, even 1 metal filling entering the compressor will destroy it.
 
J

John Crighton

Jan 1, 1970
0
Hi, I want to use the pump from an old refrigerator as an air pump.
People are constantly throwing away old refrigerators here, at council
pickup day. Would i just be able to cut the tubing and take the pump
out, or would that result in an eyeful of freon? If its pressurised,
could i csquash the tubing in a vice and then cut it there? Is there
some method which'd allow me to remove the pump on the street, without
carting the fridge back to my house?

thanks in advance, arpit thomas

Hello arpit,
your in luck, I have a couple of old fashioned fridge compressors
at my place. Not the sealed unit type. The type that sat on a tray
with an electric motor connected by a belt and a large pully wheel
on the compressor. You can have one or both if you like.

You won't be popular with your mum letting out all the stinky stuff
in the backyard if you drag an old fridge home. It makes a real
mess, believe me.
These units have been idle for twenty five years so you will
have to bear that in mind. Crickey, I didn't realise I was such
a hoarder. :)

I used a small petrol engine to drive both compressor units
for a paint spray gun. They could not supply enough air
for the spray gun.
The interesting anology with electronics is that I used a
very large tank (capacitor) and let the compressors (trickle
charger) take about 20 minutes to bring the tank up to 300
pounds per square inch of presure. (high voltage)
An old gas welding regulator (voltage regulator) was set for
30 PSI (low volts) for the spray gun and I could get roughly
5 minutes of spraying time (high current for short time) with
the petrol engine off. A bit more if it was running.

Give me an email or ring, I am in the phone book
if you want them.

Regards,
John Crighton
Hornsby Heights
 
J

John

Jan 1, 1970
0
Stop.
All refrigeration systems use a compresssable vapour to make liquid, you
cannot use a refrigeration spec compressor to 'pump' -- compress air; mainly
because the temperatures involved in compressing air (its non condensable)
are to great that the compressor will sieze/ burn out sorry.
 
R

Rheilly Phoull

Jan 1, 1970
0
John said:
Stop.
All refrigeration systems use a compresssable vapour to make liquid, you
cannot use a refrigeration spec compressor to 'pump' -- compress air; mainly
because the temperatures involved in compressing air (its non condensable)
are to great that the compressor will sieze/ burn out sorry.


Hmmm, that could be refuted I imagine ;-)

Regards ............... Rheilly Phoull
 
B

Bill

Jan 1, 1970
0
lots of people use old ac compressors as air compressors, their longevity
isn't an issue as you just chuck them out and fine another.

try to get your hands on an industrial belt drive refrigeration compressor
they have sight window to monitor the sump oil and will run for ever as long
as the oils kept up. one or two of these usually run an entire supermarket
freezer system and another very large one for the a/c system. However, they
require ~150hp 3phase motors to run them.....
 
B

Bill

Jan 1, 1970
0
running one of these motors off a domestic supply isnt possible, you'd be
best running it off an old car engine, youd then have one hell of an air
supply.
 
M

Mike Harding

Jan 1, 1970
0
Hi, I want to use the pump from an old refrigerator as an air pump.

You can buy 12V air pumps for car tyres for about $15
would they be any use to you?

Mike Harding
 
A

Arpit

Jan 1, 1970
0
Yeah, i guess with the compressor the only moving part in the thing,
it'd be the main cause of death. I found alittle bit on the internet
about taking htese compressors, and it agrees with hwat you said about
them requiring oil to survive. Providing this oil for them would
certainly be a problem. the page also said that the oil which is
pumped out is in vapour form and an extreme health hazard.
How do those cheap 50 dollar car tyre compressors circulate oil?
 
A

Arpit

Jan 1, 1970
0
would oil emissions/requirements through the air inlet cease if i used
a belt driven compressor as Mr. Crighton has so kindly offered me?
 
A

Arpit

Jan 1, 1970
0
Well, i'm sure it won't be an issue for short duty cycles like Mr.
Crighton described, however I was intending to make an air supply for
my 'workshop', without buying a noisy 3/4 hp compressor. Thus I'd need
a tank- a swap n go cylinder might be good, and I'd need to charge it
overnight I assume. I suppose a temperature switch would be a good
idea? WOuld you happen to have any idea as to the the pressure inside
a typical fridge ? I heard 10 atmospheres, is that about correct?
 
A

Arpit

Jan 1, 1970
0
lots of people use old ac compressors as air compressors, their longevity
isn't an issue as you just chuck them out and fine another.

try to get your hands on an industrial belt drive refrigeration compressor
they have sight window to monitor the sump oil and will run for ever as long
as the oils kept up. one or two of these usually run an entire supermarket
freezer system and another very large one for the a/c system. However, they
require ~150hp 3phase motors to run them.....
yes, that sounds like a nice idea, a bit beyond my scope though :)
Actually, I guess I would be using a mini one of those, since Mr
Crighton has offered me a belt driven model. I will ask him about the
oil. WHat sort of oil should be used, by the way? As you said, a car
engine would be nice, but well, might be a bit of overkill to power a
spray gun, blower ( in future perhaps drills etc) and *cough*fast
charging my potato cannon *cough* :p
 
A

Arpit

Jan 1, 1970
0
Yeah, I actually saved up and bought one some time ago to charge my
potato cannon. I paid 50 dollars though, from the local hardware
store. It doesnt really strike me as suitable to run a spray gun
directly, because of very low air output. I realise an air conditioner
won't be suitable either, but with an air conditioner compressor I can
charge a tank. THis compressor is very noisy, and inflating a 5cm
diameter pvc pipe of a meter and a half length to 100 psi is a big job
for it, it takes a long time, and gets very warm. It stikes me as a
cheap thing used for emergencies. A refrigerator compressor on the
other hand probably wou;ldn't burn out if i ran it for more than 20
minutes, and would't wake everyone if i left it to charge a tank at
night.
 
A

Arpit

Jan 1, 1970
0
Hello arpit,
your in luck, I have a couple of old fashioned fridge compressors
at my place. Not the sealed unit type. The type that sat on a tray
with an electric motor connected by a belt and a large pully wheel
on the compressor. You can have one or both if you like.

You won't be popular with your mum letting out all the stinky stuff
in the backyard if you drag an old fridge home. It makes a real
mess, believe me.
These units have been idle for twenty five years so you will
have to bear that in mind. Crickey, I didn't realise I was such
a hoarder. :)

I used a small petrol engine to drive both compressor units
for a paint spray gun. They could not supply enough air
for the spray gun.
The interesting anology with electronics is that I used a
very large tank (capacitor) and let the compressors (trickle
charger) take about 20 minutes to bring the tank up to 300
pounds per square inch of presure. (high voltage)
An old gas welding regulator (voltage regulator) was set for
30 PSI (low volts) for the spray gun and I could get roughly
5 minutes of spraying time (high current for short time) with
the petrol engine off. A bit more if it was running.

Give me an email or ring, I am in the phone book
if you want them.

Hello, thankyou very much for your generous offer :) Yes I am
actually going to be using the compressor to drive a spray gun too,
initially. Also, I'd like to use it to inflate a pvc tube with air
very quickly, and in future power air tools. Your tank idea is a very
good one, and would a LPG cylinder be suitable?( emptied of lpg of
course) :) I'm impressed you managed to get 300 psi out of the
compressors, I thoughtthey would only be able to go up to 10
atmospheres or so (147 psi). Maybe if I can find some old tanks ina
scrappyard somewhere I could run the whole system at 80 or 90 psi, and
dispense with regulators ( which sound expensive).
I would be very interested in taking such a belt driven compressor off
your hands :D Did you find you had to feed them oil? Also,would a
washing machine motor be suitable to drive it? (no idea how i'd mount
the washing machine motor, but just speculating).
So how big was your tank?
Anyway, thanks again :D
 
A

Alan Rutlidge

Jan 1, 1970
0
Hmmmm...... Lots of interesting comments, but isn't everyone forgetting
something?

It is illegal to knowingly let CFC gasses escape into the atmosphere.
Rupturing the refrigeration circulation system for the sole purpose of
recovering a compressor or the copper piping without taking the appropriate
steps to recover the gas is illegal. Ask any fridge mechanic.

Some of the comments and suggestions about purchasing a purpose built air
pump are more to the point.

Cheers,
Alan
 
B

Bill

Jan 1, 1970
0
yes, that sounds like a nice idea, a bit beyond my scope though :)
Actually, I guess I would be using a mini one of those, since Mr
Crighton has offered me a belt driven model. I will ask him about the
oil. WHat sort of oil should be used, by the way? As you said, a car
engine would be nice, but well, might be a bit of overkill to power a
spray gun, blower ( in future perhaps drills etc) and *cough*fast
charging my potato cannon *cough* :p


They have specific refrigeration oil, but since its not getting used for
that, anything will do that's remotely similar in viscosity - its not a long
term thing, but being so massively over engineered I doubt anyone could kill
one.

About the potato launcher, these compressors have upto 4 inch fittings for a
reason - there's no need to charge for a potato launcher. coupled with a
large tank and fast releasing valve, I'd see no problem in launching bowling
balls.
 
B

Bill

Jan 1, 1970
0
I some how remember 300-600Kpa for R22 gas on the high pressure side (not
the suction side) (air cons)

I think from memory its around 150 - 200Kpa on R12 / R134a as used in
domestic fridges.

Its been a bloody long time, so don't quote me.
 
B

Bill

Jan 1, 1970
0
I used to do that, but since I loved potato's so much and had a massive
lemon tree covered in thousands of lemons, I created the "lemon launcher"

IT was a bastard apon launching as you'd get lemon mist into your eyes in a
10 meter radius even with safety glasses. unless you used sealed goggles,
gee we has some fun.
 
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