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Cheap vacuum with an old fridge compressor.

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Jees

Jees

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The picture tells it.
Comp has run for over 15 years is a little deep freezer the size of a washing machine.
Vacuum for vacuum filtering or evaping BHO, sustainable living incorporates reusing assets :thumb_up:
You have to keep both the terminal tubes upwards, there's oil in the case, do not let it spit out.
 

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LOL Mindlusion. How classy :shock: :thumb_up:

PH0Man said:
Very nice! Would be cool to have pictures of the whole setup though
Click to expand...
Its just a case with an metal inlet tube (largest diameter) as the sucking side, and an outlet tube, no more. But I can do pic later no problem.

The only side that might need enlightenment is the electrical wiring because one has to emulate the thermostat with a simple on-off switch for convenience, or just a power lead only so when plugged in it simple keeps running. When spare time I will update on that.
 
Hi there!

I have used old fridge compressors for some years and am happy with them.
One should change the oil from time to time iff one uses the compressor on volatile organics.
After some acentone removals my compressor's oil got smelly and contaminated and as I didn't change it (I guess), the compressor failed one day (piston stuck). A wash bottle should be used on the low-pressure side.
I then tend to use a three-way valve to intentionally produce a small leakage in the hose. Doing so I avoid the compressor to produce a vacuum so high that it stops pumping, for this would quickly destroy the copper wirings inside the motor. Furthermore it allows to reduce the vacuum relatively slowly for safety reasons. A vacuum can be quite dangereous! E.g. the failing of a hose-junction might lead to an explosion when atmospheric pressure enters suddenly. Please keep that in mind!

This setup even allowed me to do small-scaled vacuum distillations to recycle my solvents quickly and with very little external heat. :)

Greetings, Tim
 
Nice practical info, thank you, what kind of oil did you use please to refill the compressor?
 
tryptamine9 said:
Hi there!

I have used old fridge compressors for some years and am happy with them.
One should change the oil from time to time iff one uses the compressor on volatile organics.
After some acentone removals my compressor's oil got smelly and contaminated and as I didn't change it (I guess), the compressor failed one day (piston stuck). A wash bottle should be used on the low-pressure side.
I then tend to use a three-way valve to intentionally produce a small leakage in the hose. Doing so I avoid the compressor to produce a vacuum so high that it stops pumping, for this would quickly destroy the copper wirings inside the motor. Furthermore it allows to reduce the vacuum relatively slowly for safety reasons. A vacuum can be quite dangereous! E.g. the failing of a hose-junction might lead to an explosion when atmospheric pressure enters suddenly. Please keep that in mind!

This setup even allowed me to do small-scaled vacuum distillations to recycle my solvents quickly and with very little external heat. :)

Greetings, Tim
Click to expand...


Yeah with any vacuum pump you have to change the oil often because everything you pulled out gets trapped in the oil. I only know this because I'm an HVAC technician and we use them all the time. Most of the time is says right on the pump to change the oil after every use. I change mine about once a month.

And to Jees, most refrigeration compressors use mineral oil or POE oil. I do wonder if normal vacuum pump oil would work though. It probably would.
 
Jees said:
Nice practical info, thank you, what kind of oil did you use please to refill the compressor?
Click to expand...
I did not change the oil, so this vacuum source no longer exists. :(
It worked really well for more than four years. And it was often used for acetone and naphtha.
If I had changed the oil, I would have tried mineral oil (maybe a thin two-stroke-engine oil??).


Jakup said:
Yeah with any vacuum pump you have to change the oil often because everything you pulled out gets trapped in the oil. I only know this because I'm an HVAC technician and we use them all the time. Most of the time is says right on the pump to change the oil after every use. I change mine about once a month.
Click to expand...
Maybe it is sufficient for private use, if one changed the oil as soon as plain air sucked through the pump gets exhausted smelly (solvent-like). Maybe it very much depends on WHAT you are using your pump on. Some contaminants will disturb the lubricating effect more and/or faster than others I think.
 
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