marko
7 Cubic Foot
Posts: 140
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Post by marko on Dec 29, 2021 15:01:39 GMT
The evaporator had two leaks. One was on the suction header at the evaporator left side, and the other was on a spot weld. This evaporator is made of some type of stainless steel, so I chose 56% silver flux coated rod. I would have preferred 45% blue flux, but all I had available was 56% orange. The 56% wets the stainless really well, but it is very fluid, so I capped the braze on the header with 15% sil-phos.
The skid is mostly together, but the stuffingbox gasket had to be re-visited. After days of fussing with the vacuum pump, micron gauge, manifold set, and nitrogen I finally achieved a vacuum on the compressor that never decayed to above 75 microns. The gaskets, packing, and mechanical seal all hold very well. I broke the vacuum with r152. Also, I proved that r152 burns rather well at the right flow rate, but it blows out easily at more flow.
Here is the header leak Here is the spot weld leak
This a first attempt on the header 56% silver orange rod
Spot weld leak repair Second attempt header repair, capped with 15%
Cleaned up
The skid mostly assembled The dryer is made of copper and brass, can you see where this is going?
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Post by turbokinetic on Dec 29, 2021 15:22:20 GMT
That's looking very good! It's crazy that there were multiple leaks in the evaporator. I've seen torn spot welds on the General Electric CA machines, when the compressor motor burns out and over-pressurizes the system. I wonder if the Kelvinator had developed a low-side leak and trapped a massive quantity of non-condensable gas; which over pressurized the system once the compressor stopped, and the pressures equalized?
Be careful not to ignite fluorinated refrigerants, because the resulting fumes are really bad for you. Worse than SO2, by a long way. A little bit burning from soldering operations; now and then during repairs like this, is not going to be a problem. Just be aware that the resulting fumes are very harmful and corrosive.
It looks like you are going to have frost before long on this unit! Glad the compressor seal worked out after you made the adjustments.
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marko
7 Cubic Foot
Posts: 140
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Post by marko on Dec 31, 2021 17:37:44 GMT
That's looking very good! It's crazy that there were multiple leaks in the evaporator. I've seen torn spot welds on the General Electric CA machines, when the compressor motor burns out and over-pressurizes the system. I wonder if the Kelvinator had developed a low-side leak and trapped a massive quantity of non-condensable gas; which over pressurized the system once the compressor stopped, and the pressures equalized? Be careful not to ignite fluorinated refrigerants, because the resulting fumes are really bad for you. Worse than SO2, by a long way. A little bit burning from soldering operations; now and then during repairs like this, is not going to be a problem. Just be aware that the resulting fumes are very harmful and corrosive. It looks like you are going to have frost before long on this unit! Glad the compressor seal worked out after you made the adjustments. Well now, We have frost! As far as the low side leak causing the evaporator failures, that is a possibility. The crankcase is at low side pressure, so I suppose that the mechanical seal could have introduced atmosphere, or the evaporator itself could have done it. Personally, I am inclined to believe that technician error caused the spot weld failure. Now, I just have to pump it down and finish the cabinet restoration. Body and paint work, plus all the little detail stuff.
Ain't it funny how the simplest things in life bring such great satisfaction! Thank God |
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Post by turbokinetic on Dec 31, 2021 18:25:24 GMT
That's looking very good! It's crazy that there were multiple leaks in the evaporator. I've seen torn spot welds on the General Electric CA machines, when the compressor motor burns out and over-pressurizes the system. I wonder if the Kelvinator had developed a low-side leak and trapped a massive quantity of non-condensable gas; which over pressurized the system once the compressor stopped, and the pressures equalized? Be careful not to ignite fluorinated refrigerants, because the resulting fumes are really bad for you. Worse than SO2, by a long way. A little bit burning from soldering operations; now and then during repairs like this, is not going to be a problem. Just be aware that the resulting fumes are very harmful and corrosive. It looks like you are going to have frost before long on this unit! Glad the compressor seal worked out after you made the adjustments. Well now, We have frost! As far as the low side leak causing the evaporator failures, that is a possibility. The crankcase is at low side pressure, so I suppose that the mechanical seal could have introduced atmosphere, or the evaporator itself could have done it. Personally, I am inclined to believe that technician error caused the spot weld failure. Now, I just have to pump it down and finish the cabinet restoration. Body and paint work, plus all the little detail stuff.
Ain't it funny how the simplest things in life bring such great satisfaction! Thank God <button disabled="" class="c-attachment-insert--linked o-btn--sm">Attachment Deleted</button> <button disabled="" class="c-attachment-insert--linked o-btn--sm">Attachment Deleted</button> <button disabled="" class="c-attachment-insert--linked o-btn--sm">Attachment Deleted</button>
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Yay!!! That is excellent news! I am sure it has brought you a massive amount of satisfaction. Really do know how that feels, too. There have been some exploded evaporators from people getting carried away with nitrogen pressure before. Something about trying to reverse flush the capillary tube by pressurizing the evaporator from the return line and there was a very loud bang..... Thanks for sharing your progress with us! I'm sure you can't wait to get the cabinet back together! |
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Post by turbokinetic on Dec 31, 2021 18:27:18 GMT
That whole thing looks amazing; but I am really digging the polished up drier!
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marko
7 Cubic Foot
Posts: 140
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Post by marko on Dec 31, 2021 19:42:01 GMT
That whole thing looks amazing; but I am really digging the polished up drier! Sorry, I can't help myself... polished copper and brass is a stumbling block of mine. I washed the silica gel with a/c system flush and baked it in the oven at 250F for a few hours, so it is a functional dryer. Also, the little Supco SG-114 that you recommended is a great feature.
BTW, I just did a trial pump out, although it took several minutes, all of the refrigerant is contained in the condenser and receiver. Evacuating the evap and line set should be all that is required to make it go. I still have two cans of blow out just in case.
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Post by turbokinetic on Jan 1, 2022 14:07:41 GMT
That whole thing looks amazing; but I am really digging the polished up drier! Sorry, I can't help myself... polished copper and brass is a stumbling block of mine. I washed the silica gel with a/c system flush and baked it in the oven at 250F for a few hours, so it is a functional dryer. Also, the little Supco SG-114 that you recommended is a great feature.
BTW, I just did a trial pump out, although it took several minutes, all of the refrigerant is contained in the condenser and receiver. Evacuating the evap and line set should be all that is required to make it go. I still have two cans of blow out just in case.
I think we all probably like polished copper and brass, or we wouldn't be in this field LOL! The pump-down function is always nice to have, when you're working with a system like this. The belt driven Frigidaires also have that function and it's very handy when making adjustments to the float in the evaporator. |
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marko
7 Cubic Foot
Posts: 140
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Post by marko on Apr 1, 2022 20:53:02 GMT
I changed the title of this thread since I discovered that my box is a 1932 and not a 1933.
The bodywork and finish items are not coming quickly. I made a major mistake by stripping the paint with a flapper wheel on a 4" grinder and warping the cabinet. The upper edge of the cabinet metal is not hemmed or restrained in any way, other than the hat on top. Now removing this warp has become a major sheet metal finishing problem. It is 16 gauge, making the task more labor intensive. Lesson learned: use paint remover, never grind the paint off old (or new) sheet metal.
I did successfully cast new shelf standards out of urethane rubber, and was able to re-finish the porcelain box and door interior with tub and tile epoxy finish. It's good enough. I also cast new breaker strip corner rubbers, and made a junction box cover for the motor.
One other last item, which I will attempt to reproduce, by hammer forming sheet metal, is the missing motor/compressor door.
Maybe I can upload a few pictures in the near future!
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Post by ckfan on Apr 1, 2022 22:22:01 GMT
Oof, sorry to hear about the warped metal. Glad that you’re still making progress on it though. It should be a very nice piece when you’re done!
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Post by turbokinetic on Apr 2, 2022 14:29:39 GMT
I changed the title of this thread since I discovered that my box is a 1932 and not a 1933.
The bodywork and finish items are not coming quickly. I made a major mistake by stripping the paint with a flapper wheel on a 4" grinder and warping the cabinet. The upper edge of the cabinet metal is not hemmed or restrained in any way, other than the hat on top. Now removing this warp has become a major sheet metal finishing problem. It is 16 gauge, making the task more labor intensive. Lesson learned: use paint remover, never grind the paint off old (or new) sheet metal.
I did successfully cast new shelf standards out of urethane rubber, and was able to re-finish the porcelain box and door interior with tub and tile epoxy finish. It's good enough. I also cast new breaker strip corner rubbers, and made a junction box cover for the motor.
One other last item, which I will attempt to reproduce, by hammer forming sheet metal, is the missing motor/compressor door.
Maybe I can upload a few pictures in the near future!
It's frustrating that the metal warped from the heat of the grinder flap disc. So frustrating! I am confident you'll be able to get it restored to like-new, however. Hope to see pictures of your new compressor door, when that project comes to fruition! |
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Post by douro20 on Apr 2, 2022 23:17:09 GMT
Wow,that's really neat! Is that a Packard? Packard boasted about having the first cars with air conditioning! I never saw anything like that before!! I believe the Packard system was one which was built-in to the back of the vehicle. They sold them with air conditioning from the factory. |
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Post by douro20 on Apr 2, 2022 23:22:44 GMT
A Weiler stripping tool on an electric drill would probably had worked better without warping the metal.
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marko
7 Cubic Foot
Posts: 140
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Post by marko on Jun 3, 2022 20:04:25 GMT
A quick update: The cabinet is 90% back together and painted; just waiting on the trims, breaker strips, top and door. I put the evaporator in, made the freon pipes, evacuated the lines and evap and opened the king valves. The system took 4 oz. more of 152a, and I put the remaining 4 oz. in because the receiver is big enough to hold it. I ran the system for several shake down runs of a few hours each and noticed oil in the chiller tray, so I pumped the system down and pulled the evaporator. an N2 test revealed more holes than a piece of Swiss cheese. Several hours of silver brazing and pressure testing (under water) revealed no more leaks, so I hope to have the machine built by the end of the weekend!
BTW, A very special thanks to Turbokinetic for his excellent suggestion of using r600 to recharge the failed t'stat, worked like a dream!
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Post by turbokinetic on Jun 4, 2022 12:25:11 GMT
A quick update: The cabinet is 90% back together and painted; just waiting on the trims, breaker strips, top and door. I put the evaporator in, made the freon pipes, evacuated the lines and evap and opened the king valves. The system took 4 oz. more of 152a, and I put the remaining 4 oz. in because the receiver is big enough to hold it. I ran the system for several shake down runs of a few hours each and noticed oil in the chiller tray, so I pumped the system down and pulled the evaporator. an N2 test revealed more holes than a piece of Swiss cheese. Several hours of silver brazing and pressure testing (under water) revealed no more leaks, so I hope to have the machine built by the end of the weekend!
BTW, A very special thanks to Turbokinetic for his excellent suggestion of using r600 to recharge the failed t'stat, worked like a dream!
That is so frustrating about the evaporator leaking in so many places! It's as if the metal may have had some sort of alloy defect leaving it vulnerable to corrosion from SO2 over the years. Happy to have assisted with the thermostat, as well! |
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marko
7 Cubic Foot
Posts: 140
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Post by marko on Jun 7, 2022 21:10:12 GMT
Well now, I have a cold box! The TD on the stat is wide. The only way from here is to adjust the bellows screw.
I found another Ranco Type KW on FeePay to use for parts and reference. For now, the machine runs most of the time bringing my beverage of choice down to temp. Beer freezes at 29F. The air temp gets down in the mid 20's, run time is long. I adjusted the AXV almost max for mass of refrigerant flow, it drops the temp faster that way, but too far will slug on start up, so backed it up a bit. So far, still have full column of liquid behind the AXV. Test, adjust, re-test, adjust..... That is why I do not like doing refrigeration work for a living. The upside? My beverages are truly ice-cold, and I can relax at home.It is not work from here! VBG!
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