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Post by cablehack on Jul 2, 2014 1:53:21 GMT
Thanks for opening up the tube...what an interesting coincidence that the first hole is cleanest. When the float valve stuck in my CA-2, that was where the last of the refrigerant emerged from. If there was equal suction on all the other holes then they should have produced refrigerant too, but they never did. It also makes sense that when I unblocked the evaporator that if one hole gave way, then there wouldn't be the pressure to clear the others.
I'm now beginning to wonder if prior to the R22 cleanout, that was the only hole allowing refrigerant through. Maybe it's the other holes now operating that has been the main cause for the improvement in operation; lower temp & longer off time.
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Post by coldspaces on Jul 2, 2014 4:19:49 GMT
Any ideas on what size those holes are? I have to assume they are mighty small for the little amount of refrigerant that is expected to "spray" out of them, so to speak? Haven't checked the hole size but knew the question would be asked. I will try to measure them and report back. |
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Post by coldspaces on Jul 2, 2014 16:49:16 GMT
Looks like all 5 holes are the same at about .030
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Post by blackhorse on Sept 21, 2014 16:23:53 GMT
Thank you very much for that. Nothing really seems to let you appreciate the design like seeing the actual structure.
I have to say that really seems insanely complex for what would seem like would work just fine as a gravity feed flooded evaporator.
The routing of all that tubing inside the formed passages in the stainless.
I would love it if the actual guys who designed some of these things had ever put to paper their reasoning behind various design features.
And I wonder what the reasoning was behind the completely different formate machines being built as a parallel line for just a few years, while the SO2 machines were offered before, after, and at the same time.
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Post by cablehack on Sept 21, 2014 23:37:21 GMT
Thank you very much for that. Nothing really seems to let you appreciate the design like seeing the actual structure. I have to say that really seems insanely complex for what would seem like would work just fine as a gravity feed flooded evaporator. The routing of all that tubing inside the formed passages in the stainless. I would love it if the actual guys who designed some of these things had ever put to paper their reasoning behind various design features. And I wonder what the reasoning was behind the completely different formate machines being built as a parallel line for just a few years, while the SO2 machines were offered before, after, and at the same time. The patents are probably the best insight to why things were designed as they are, as well as a couple of revelations by ex GE employees. The way the CA evaporator was constructed also probably has a lot to do with it being assembled flat then folded into the final shape. The idea behind methyl formate machines was that being a safer refrigerant, it would overcome all the problems of SO2 (nasty smell, sulphuric acid, etc). It appears from the patents GE started experimenting with it around 1929 but had to overcome problems with formic acid and non condensable gas formation. This they did with certain additives and the first CA's became available late 1932 to replace the DR1 and DR2 machines. During 1933 and the first half of 1934 there were no SO2 Monitor Tops, but there were conventional open compressor Flatops using SO2, for those who couldn't afford the more expensive hermetic Monitor Top. (Why there was no CA-3 is still unknown - it seems the DR3 served this purpose until mid 1934 when the SO2 CK-3 became available). Once the original CA machines (form A) went into service, it was found that NCG's could still be a problem, so it was redesigned to increase time between purges; hence the form B machine, this being done by increasing the size of the float chamber, and including a bypass to allow the compressor dome to also function as an NCG accumulator. But, with an army of servicemen having to maintain these fridges it was obviously a problem, which is why GE reverted back to using SO2. The CA form B was basically redesigned with a scotch yoke compressor, filled with SO2, and evolved into the CK. It seems that GE did not want to pay royalties on other companies patents, so put off using Frigidaire's Freon 12 for as long as they could. The William Holladay story monitortop.freeforums.net/thread/29/william-holladay-article-history-monitor gives a useful insight into the story. Also have a read of this 1934 sales bulletin members.iinet.net.au/~cool386/ge_service/1934sales.pdf Here you'll see that the CA-1 form B was the last of the methyl formate machines on sale. |
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Post by ChrisJ on Sept 22, 2014 13:25:37 GMT
Thank you very much for that. Nothing really seems to let you appreciate the design like seeing the actual structure. I have to say that really seems insanely complex for what would seem like would work just fine as a gravity feed flooded evaporator. The routing of all that tubing inside the formed passages in the stainless. I would love it if the actual guys who designed some of these things had ever put to paper their reasoning behind various design features. And I wonder what the reasoning was behind the completely different formate machines being built as a parallel line for just a few years, while the SO2 machines were offered before, after, and at the same time. The patents are probably the best insight to why things were designed as they are, as well as a couple of revelations by ex GE employees. The way the CA evaporator was constructed also probably has a lot to do with it being assembled flat then folded into the final shape. The idea behind methyl formate machines was that being a safer refrigerant, it would overcome all the problems of SO2 (nasty smell, sulphuric acid, etc). It appears from the patents GE started experimenting with it around 1929 but had to overcome problems with formic acid and non condensable gas formation. This they did with certain additives and the first CA's became available late 1932 to replace the DR1 and DR2 machines. During 1933 and the first half of 1934 there were no SO2 Monitor Tops, but there were conventional open compressor Flatops using SO2, for those who couldn't afford the more expensive hermetic Monitor Top. (Why there was no CA-3 is still unknown - it seems the DR3 served this purpose until mid 1934 when the SO2 CK-3 became available). Once the original CA machines (form A) went into service, it was found that NCG's could still be a problem, so it was redesigned to increase time between purges; hence the form B machine, this being done by increasing the size of the float chamber, and including a bypass to allow the compressor dome to also function as an NCG accumulator. But, with an army of servicemen having to maintain these fridges it was obviously a problem, which is why GE reverted back to using SO2. The CA form B was basically redesigned with a scotch yoke compressor, filled with SO2, and evolved into the CK. It seems that GE did not want to pay royalties on other companies patents, so put off using Frigidaire's Freon 12 for as long as they could. The William Holladay story monitortop.freeforums.net/thread/29/william-holladay-article-history-monitor gives a useful insight into the story. Also have a read of this 1934 sales bulletin members.iinet.net.au/~cool386/ge_service/1934sales.pdf Here you'll see that the CA-1 form B was the last of the methyl formate machines on sale. It's amazing we knew none of this around a year ago or so or has it been longer now? |
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Post by cablehack on Sept 22, 2014 23:27:02 GMT
It's amazing we knew none of this around a year ago or so or has it been longer now? Yeah it's been an amazing achievement, and one everyone should be proud of. It's been a bit over two years since things started to take off on the flickr group, but the catalyst with the CA machines was getting the complete service manual, I think that was around the time I'd got the CA-1 working, a year ago now. |
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Post by blackhorse on Oct 11, 2014 17:24:36 GMT
Thank you very much for that. Nothing really seems to let you appreciate the design like seeing the actual structure. I have to say that really seems insanely complex for what would seem like would work just fine as a gravity feed flooded evaporator. The routing of all that tubing inside the formed passages in the stainless. I would love it if the actual guys who designed some of these things had ever put to paper their reasoning behind various design features. And I wonder what the reasoning was behind the completely different formate machines being built as a parallel line for just a few years, while the SO2 machines were offered before, after, and at the same time. The patents are probably the best insight to why things were designed as they are, as well as a couple of revelations by ex GE employees. The way the CA evaporator was constructed also probably has a lot to do with it being assembled flat then folded into the final shape. The idea behind methyl formate machines was that being a safer refrigerant, it would overcome all the problems of SO2 (nasty smell, sulphuric acid, etc). It appears from the patents GE started experimenting with it around 1929 but had to overcome problems with formic acid and non condensable gas formation. This they did with certain additives and the first CA's became available late 1932 to replace the DR1 and DR2 machines. During 1933 and the first half of 1934 there were no SO2 Monitor Tops, but there were conventional open compressor Flatops using SO2, for those who couldn't afford the more expensive hermetic Monitor Top. (Why there was no CA-3 is still unknown - it seems the DR3 served this purpose until mid 1934 when the SO2 CK-3 became available). Once the original CA machines (form A) went into service, it was found that NCG's could still be a problem, so it was redesigned to increase time between purges; hence the form B machine, this being done by increasing the size of the float chamber, and including a bypass to allow the compressor dome to also function as an NCG accumulator. But, with an army of servicemen having to maintain these fridges it was obviously a problem, which is why GE reverted back to using SO2. The CA form B was basically redesigned with a scotch yoke compressor, filled with SO2, and evolved into the CK. It seems that GE did not want to pay royalties on other companies patents, so put off using Frigidaire's Freon 12 for as long as they could. The William Holladay story monitortop.freeforums.net/thread/29/william-holladay-article-history-monitor gives a useful insight into the story. Also have a read of this 1934 sales bulletin members.iinet.net.au/~cool386/ge_service/1934sales.pdf Here you'll see that the CA-1 form B was the last of the methyl formate machines on sale. Thank you very much for those links; I especially enjoyed the Holladay history PDF, it answers several questions about the unique evaporator on those machines. I wonder how many of those cast-iron freezing plates got shot out of an open window, and how that number compares to the number of broken toes during the same time frame......... |
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Post by andrewk on Sept 20, 2020 6:00:49 GMT
My CA-2-B16 has been puttering along now since my grandparents bought it new in the early 30's. It even spent 40 years outdoors under a patio awning not far from the ocean. Some of the wiring cracked from old age when i moved it, so i had to rewire it, install a cartridge heater, and restored the cabinet.... but mechanically it runs great.
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Post by elec573 on Oct 14, 2020 4:37:55 GMT
Glad you’re carrying on with the ca . So many people would not. Just wondering if you checked it for ncg’s? After that many years i would think it would have some.
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