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

POLAND_SPUD · Posted: 12/17/2007 4:44 AM Post subject:

My compressor is a a part of refrigerator. It can pump to 300 psi and more (it is said that 35 atm is possible with this - but I've never tried that). It has much smaller flow that 'normal' comercially available compressors. Therefore it is ideal for small chamber-high pressure designes.

How to build one:

1. First of all this thing is basicly a part of a fridge - it is a pump that pumps freon gas (newer fridges use more enviroment-firendly gas) throught those small copper pipes and a radiator thing that are on the back of any fridge. The pump is the only thing you need.

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 junkyards have them.
If you decide to remove the compressor you risk releasing freon to the atmosphere. Most new fridges don't use freon any more - but I have no idea how to find out whether a given fridge uses freon or not. Anyway to remove the pump you have to cut those thin copper pipes ( 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 thing is not needed ). finally, remove the compressor

3. 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 . All you have to do is to connect the cable to the power and add a switch to turn it on/off.
One of the pipes 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.
Now all you have to do is to put/connect an airhose with the pipe that is an air output and fasten it with a clamp tightly. that's all - your compressor is ready to work

4. 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 - I strongly suggest you to add one - connect the airhose with a gauge and a safety valve. 300 psi pressures are more dangerous than 8 atm of commercial aircompressor so make sure you know what you are doing, especially if you are planning to use it to pump a PCV spudgun. Every refrigator pump/compressor can be different - I don't guarrante you that the one you will find can get 400 psi. Mine works fine at 300 psi and I've heard that they even do 35 atm but as I said before this part was not constructed 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

EDIT
I tried to correct the text + I added a diagram..I hope it's easier to understand it now (if there are any mistakes, ideas how to rewrite it etc. - PM me please)