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Post by jhigdon2 on Dec 7, 2014 2:58:17 GMT
Well I'm back, and I've been recently working on a CA 2 B. I've decided to finally try an alternative refrigerant. R123. The machine is one I've had for awhile and was seized when I got it. Of coarse it had the usual bad float seat and a bad check valve also. After remedying those problems, I evacuated and charged with 800 ml of R123. So far I haven't finalized the charge, and am going to let it sit for a day with oil heater on to let the refrigerant flow into the evap . I keep you posted on the results. For better or worse.
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Post by coldspaces on Dec 7, 2014 3:16:05 GMT
Sweet more experimentation, will be watching.
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Post by allan on Dec 7, 2014 3:28:12 GMT
Well I'm back, and I've been recently working on a CA 2 B. I've decided to finally try an alternative refrigerant. R123. The machine is one I've had for awhile and was seized when I got it. Of coarse it had the usual bad float seat and a bad check valve also. After remedying those problems, I evacuated and charged with 800 ml of R123. So far I haven't finalized the charge, and am going to let it sit for a day with oil heater on to let the refrigerant flow into the evap . I keep you posted on the results. For better or worse. Alright!! The CA doc is in |
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Post by jhigdon2 on Dec 7, 2014 3:37:02 GMT
So far I'm pretty hopeful about this experiment. I turned it on a couple of times for just a few minutes and it cooled very quickly. Compressor is dead quiet. Got down to a 6 deg evap quickly.
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Post by allan on Dec 7, 2014 4:10:19 GMT
So far I'm pretty hopeful about this experiment. I turned it on a couple of times for just a few minutes and it cooled very quickly. Compressor is dead quiet. Got down to a 6 deg evap quickly. It likes that new stuff! |
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Post by ChrisJ on Dec 7, 2014 4:15:52 GMT
Did you drain all of the original oil and lard out?
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Post by blackhorse on Dec 7, 2014 6:10:38 GMT
You know, if you aren't really careful with that, you could end up making a CA stable and maintenance-free for the rest of it's life.
What a radical departure from normal that would be--
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Post by blackhorse on Dec 7, 2014 6:13:30 GMT
Did you drain all of the original oil and lard out? How exactly would you do that? The only way that comes immediately to mind would be to turn it upside down and vacuum-pump through the condenser and float valve port into a receiving container. Is that practical? |
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Post by ChrisJ on Dec 7, 2014 12:13:51 GMT
Did you drain all of the original oil and lard out? How exactly would you do that? The only way that comes immediately to mind would be to turn it upside down and vacuum-pump through the condenser and float valve port into a receiving container. Is that practical? That won't work with a CA as the exhaust line protrudes into the compressor housing quite far to avoid just that. I believe Mr Higdon has done it before by drilling and tapping the bottom of the housing. |
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Post by jhigdon2 on Dec 7, 2014 17:14:39 GMT
Yeah. On a CA you have to drill a hole in bottom of compressor to drain it. I didn't change the oil in this one. I just wanted to see if R123 would even cool in one of these. I started the unit this morn. It seems to cool well and runs quiet. Frost line is low however, so I'll have to add more refrigerant. I may also have to mess around with cap tube sizing, but that will most likely be another day. Another problem is that I have no idea of miscability with this stuff with mineral oil. Lots of thinking to do yet.
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Post by blackhorse on Dec 7, 2014 18:34:10 GMT
*Shudders*
How do you keep metal shavings from drilling and tapping from getting in the compressor?
I've done similar with truck axles and machinery drives, but those are things you can flush while you're drilling and tapping. Even using magnetized tools and flushing some gets in; I always use a plug with a magnet in it when I do that, and I get shavings on the magnet the next time I drain the oil.
Along the same subject, some of the Seeger rotary compressors I have opened have a little round magnet in the bottom of the sump.
And some of the better cows have a magnet in the bottom of their sump.
Yes.
They do.
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Post by jhigdon2 on Dec 7, 2014 19:04:57 GMT
A little grease on the drill bit and a drill stop to keep from plunging. That's about the best a guy can do. Gives me shudders to. Luckily mineral oil is non detergent and cannot suspend foreign material, so hopefully if there's a metal chip or two, it will just lay in the bottom of sump.
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Post by ChrisJ on Dec 7, 2014 19:46:18 GMT
Assuming R123 can carry the oil back, does the frost line even matter aside from cooling capacity?
Would be a wonderful thing if it didn't.
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Post by blackhorse on Dec 7, 2014 21:09:05 GMT
Assuming R123 can carry the oil back, does the frost line even matter aside from cooling capacity? Would be a wonderful thing if it didn't. I would say that it certainly does. After GE changed to R-12, (miscible with mineral oil) they still had the frost line half way up the accumulator tank or more. And do we have any definitive information on oil return for any kind of oil with R123? And of course there's superheat to consider; a lower refrigerant level would mean hotter discharge gas. And there's the more-than-odd design of the "pig" evaporators; would there be enough refrigerant-to-brine contact if the level were lower? There are enough design variables that I would be inclined to get as close to the original level as reasonable. And I totally agree with this project, and applaud the effort. It's exactly what I would do if/when I have a formate unit. |
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Post by blackhorse on Dec 7, 2014 21:15:19 GMT
Hey, something--
If the metal shavings concern you, I have seen offered for sale powerful magnets that are intended to be stuck to engine oil pans, for those who have less than complete faith in oil filters.
I would think that one of those, or a suitable powerful magnet like the ones you can salvage from old hard drives, stuck to the bottom of the compressor housing, would trap and hold any stray bits on the inside.
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