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andersnielsen45
07-06-2009, 09:20 PM
I am building a sluchice machine for my dormitory kitchen. The plan is to use an old 160 W hermetic compressor from a R12 freezer. I’m interested in building a new evaporator that is better for the purpose of making sluchice. This of cause involves discharging the old system and recharging the new one. The problem is that I have no practical experience or access to special tools like vacuum pumps and so on. The plan is to recharge the system with R290 Propane, because I can get access to propane and it seems I will deal with similar pressures ass the originally R12 filling. I have the following questions:


Will I kill myself in the process, in some exploration?
Will I kill my friends because the compressor makes a spark later on?
How do I calculate the filling size?
Can I use ordinary camping gas?
How do I empty the system for air and R12 without a vacuum pump? (Is it may be possible just to dilute by blowing propane thru the system for a while?)
Where do I find a good expansion valve solution (not to expensive)

Hope you can help me, maybe even save the life of me and my friends. If you know a place where I can find guides or other relevant material please let me know

Brian_UK
07-06-2009, 11:16 PM
Will I kill myself in the process, in some exploration?



Anything is possible.

Will I kill my friends because the compressor makes a spark later on?There should not be an explosive mixture inside the system if done correctly.

How do I calculate the filling size?Do it by sub-cooling method or by superheat as you are using an expansion valve.

Can I use ordinary camping gas?No, the quality is not good enough.

How do I empty the system for air and R12 without a vacuum pump? (Is it may be possible just to dilute by blowing propane thru the system for a while?)By using a recovery machine. Your choice of 'blowing' it through is illegal as well as dangerous. No refrigerants may be discharged to atmosphere.

Where do I find a good expansion valve solution (not to expensive)Contact your local refrigeration wholesaler/supplier.



If you know a place where I can find guides or other relevant material please let me know Well, you've started here but there is a vast range of information out there via the wonders of Google. ;)

icecube51
08-06-2009, 04:11 PM
Oeps, if we don't here from that guy again in a few days,we now why!!! the wonders of Propane.(LOL)

Ice

Gary
08-06-2009, 05:39 PM
Hmmmm...

No knowledge.

No experience.

No tools.

Non-standard components.

Non-standard refrigerant.

Dangerous refrigerant.

What's wrong with this picture?

Is there anything right with this picture?

andersnielsen45
08-06-2009, 08:18 PM
I hear what you are saying:) of cause not the answer I was hoping for, but on the other hand sort of what I was expecting.
It would be so cool to make this work with a homemade evaporator. Now I think I will use a brine to cool my slush-ice production surface, this way I can use the existing evaporator.
Thanks for your replies.
If anyone has other ideas for the project please let me know

Gary
08-06-2009, 09:13 PM
As a beginner project, I would suggest finding a cheap system that works, take it all apart, put it all back together, and make it work again. If you can accomplish this, you may be ready for the next step.

Brian_UK
08-06-2009, 10:52 PM
As Gary says but with the right equipment to hand.