My compressor, 300 psi and more (..... much more :-D )

[POLAND_SPUD]

The fridge compressor is a refrigeration compressor adapted as an air compressor. While most shop compressors can reach up to 120 psi this thing can reach up to 500 psi and more.

How to build one:

1. First of all, this thing is basically a part of a fridge - it is a pump that pumps freon gas (newer fridges use some more environment-friendly gas) through those small copper tubes on the back of any fridge.


2. There are several ways to find get this part: you can remove it yourself or you can buy it - they are sold as spare parts and I heard that some junk-yards have them.

3. To cut out the pump you have to cut those thin copper tubes ( cut about 15 - 20 cm from the pump ) and cut the cable (so that there is only that cable that goes to the pump - that thermostat thingy is not needed ).


4. Provided you did everything in the right way the compressor you have just removed has 3 copper pipes sticking out of it and a cable. One of the tubes is an air inlet and the other one is where the air comes out, that 3rd pipe is already closed - it was used to fill the fridge with gas - it's not important.

5. Connect the cable to the power and add just any on/off switch (of course one rated to 115/230V (depending where you live) but I guess it goes without saying.

6. Now all you have to do is to connect the output tube with the rest of your setup. You can use a home-made compression fitting (that's the method I use), some people prefer to solder it. Back when I posted this thread I just used an air hose and a simple clamp.

7. It is advised to add an air filter to the pump - it doesn't have to be an off the shelf part - you can make your own air filter - a pen tube with some cotton inside would suffice (make sure that the cotton can't be sucked into the pump ) join the air filter with the pipe that is an air inlet and that's all


important note ---> There is no safety valve in it and it can generate pressures that are very very dangerous. This part was not designed to pump air into spudguns --> so you probably won't find information "it is 100% safe to use the compressor for spudding" in any fridge manual.
You should make sure that all the parts used in your setup can handle pressures it can generate. You should add a safety valve/rupture this to your setup.


EDIT #3
I rewrote the text - I fixed YT links & added a playlist instead


Here's my playlist on them - I'll be adding more videos to it when I have time, but it should answer some questions regarding removing them & wiring

Hopefully I'll have time to create a new version of this tutorial soon

[Fnord]

How much flow do you think you are getting from this thing?

I just happen to have one of these sitting upstairs, though I intended to use it as a vacuum pump for a co2 laser.

Anyone selling znse lenses ?

[POLAND_SPUD]

A guesstimate - 1.27 cm X 150 cm chamber to 250 psi in about 80 seconds - I would say that its flow is similar to a bike pump - only that it doesn't slow down when the pressure rises... so it no good for a bbmg. It can pump to high pressure but flow is lower. ahhh i forgot to add --->I advise to use quick connect fittings with this becasue the addapter to shreader valve is pushed by pressure from the valve at >200 psi.... so you have to press it to a shreader valve by hand

[jackssmirkingrevenge]

I advise to use quick connect fittings with this becasue the addapter to shreader valve is pushed by pressure from the valve at >200 psi....

Alternatively, you can get a threaded connection for schraders, like the ones used in shock pumps.

I really need to get my hands on another one of these as it seems my initial judgement of the setup was based on a faulty part.

[bluerussetboy]

i have friends who used these pumps in their 4x4s. it took forever to air up 4 tires from 6 psi to 25 psi. they have upgraded to CO2 or Nitrogen tanks.

i imagine a smaller chamber wouldn't be to unbearable.

occasionally i help my neighbor at his appliance store replacing parts and from what i've seen compressors are one of the first things to go out on a refrigerator, so finding a junk refrigerator with a good compressor is hard. locally compressors run about $65 minimum. even the ones that can be repaired the parts kits are about $30.

[POLAND_SPUD]

bluerussetboy... this thing is for small chambers/high pressures - like 100 cm3. It takes some time to pump 4 car tires even with a foot pump - tires have much greater volume than most spudguns...

hmm here poland I can buy them for 30 PLN, which is more less 15$.
yes they are generally the first and only thing to go out in a refrigerator - becasue this is the only moving/working part in a refrigerator....

not all of junk refrigators are broken down - some were disposed of becasue they were old. The one I use is from 15 years old freezer...

[Killjoy]

Son of a bitch, I wish this was around a 2 weeks ago, cause I chucked a fridge and a freezer then. Grrrr....

This is a great idea though, i see a trip to the thrift store in my future for an old fridge.

[Antonio]

I really like this idea. I never knew refrigerators pumps could go up to such a high pressure! Impressive. I should go check out the scrap yard now:)

[rna_duelers]

Releasing Freon into the atmosphere is against the law in most places by the way,so don't get caught.

And I am definitely going to do this next time one of your fridges or something goes pop.Hopefully the pump survives.

[SleekZ]

apparently air conditioner compressors are pretty good too.

[POLAND_SPUD]

It's capable of 35 atm.( that is 507 psi) althought I've never tried these pressures for safety reasons and because I don't even have a gauge for such high pressures

I have it for quite a long time and it still works perfectly... I spend about 1$ and two hours to make this this or even less so I think it is great.

[Killjoy]

Releasing Freon into the atmosphere is against the law in most places by the way,so don't get caught.

True, but I don't think a lot of people care.
When we chucked our freezer we had to pay a a guy to come and certify that there wasn't any freon (even though the freon had already leaked out). Afterwards though he told us that next time we can let the freon out and just cut the compressor out ourselves, and then we can dump it no problems, and save ourselves $30 bucks.

[ALIHISGREAT]

any ideas where to get one from? the rubbish tip near me won't let me have one

[POLAND_SPUD]

Yesterday I added a quick-connect fittings so the total cost of my compressor has increased from about 1$ to 5 $


and I've tried pumping past 300 psi - possibly near 350 - 380 - (sorry I don't know exactly becasue my gauge is limmited to 300 psi...) I've used earplugs but I still hear ringing in my ears...

[Carlman]

so how loud is this thing for certain pressures?

im in ozzie surburbia and i think every time my neighbors hear the compressor they start talking louder than usual to try to scare me lol (it works...)