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Post by jhigdon2 on Dec 9, 2014 4:33:22 GMT
Yeah. I'm looking forward to it fur sure. Lol. I've got a heavy workload most of the week, so I'm gonna have to put this thing on the back burner until Thurs or fri. Just take it easy on the back. We don't need that giving out. |
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Post by jhigdon2 on Dec 9, 2014 4:42:12 GMT
Yes for sure on that. Feeling pretty good lately,still some numbness on the left side, which makes picking up screws ect a little tedious, but as long as I don't try to wrestle a DR3 around, I think I'll be ok. Lol
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Post by blackhorse on Dec 9, 2014 5:03:39 GMT
Yes for sure on that. Feeling pretty good lately,still some numbness on the left side, which makes picking up screws ect a little tedious, but as long as I don't try to wrestle a DR3 around, I think I'll be ok. Lol You too? I'm still regretting moving a display freezer at the local general store about 20 years ago. It takes about 3 days of rest every time I get physical. >.< |
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Post by jhigdon2 on Dec 10, 2014 20:16:23 GMT
Ok. Had some time spend with the CA today. At this point I have 30" of .031 cap tube on it and bumped the charge up a bit. Now have 1.5 litre of R123 in it. It now has a nearly fully frosted evap and just the front edges of the rt side tank are not frosting. Evap temp is 15 deg in some spots and down to 6 degrees in other areas. Compressor is whisper quiet and run amps are about 2.5.
In summery I am alot closer than I was a few days ago. Still may need to do some cap tube adjustments. I'll sleep on it and wage another attack this weekend.
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Post by blackhorse on Dec 10, 2014 23:01:40 GMT
Ok. Had some time spend with the CA today. At this point I have 30" of .031 cap tube on it and bumped the charge up a bit. Now have 1.5 litre of R123 in it. It now has a nearly fully frosted evap and just the front edges of the rt side tank are not frosting. Evap temp is 15 deg in some spots and down to 6 degrees in other areas. Compressor is whisper quiet and run amps are about 2.5. In summery I am alot closer than I was a few days ago. Still may need to do some cap tube adjustments. I'll sleep on it and wage another attack this weekend. Sounds pretty damn close to me. Are the sides of the evap evenly frosted? Just an aside; if you are using one of those IR non-contact thermometers (point and shoot), they vary quite a bit on the exact same temp, depending on the nature of the surface. Even the Fluke, which is pretty top-line, can vary as much as 12F, and be completely within the specs the factory rep gives. If the angle or frost coating or flat-or-ripply is different the reading can vary even though you are spot-on. I just got readings 14F through 28F on my CK, off just before starting, not counting the tank. |
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Post by ChrisJ on Dec 11, 2014 0:30:44 GMT
Ok. Had some time spend with the CA today. At this point I have 30" of .031 cap tube on it and bumped the charge up a bit. Now have 1.5 litre of R123 in it. It now has a nearly fully frosted evap and just the front edges of the rt side tank are not frosting. Evap temp is 15 deg in some spots and down to 6 degrees in other areas. Compressor is whisper quiet and run amps are about 2.5. In summery I am alot closer than I was a few days ago. Still may need to do some cap tube adjustments. I'll sleep on it and wage another attack this weekend. Sounds pretty damn close to me. Are the sides of the evap evenly frosted? Just an aside; if you are using one of those IR non-contact thermometers (point and shoot), they vary quite a bit on the exact same temp, depending on the nature of the surface. Even the Fluke, which is pretty top-line, can vary as much as 12F, and be completely within the specs the factory rep gives. If the angle or frost coating or flat-or-ripply is different the reading can vary even though you are spot-on.I just got readings 14F through 28F on my CK, off just before starting, not counting the tank. These are my findings as well which is why I switched to DMM and thermalcouples. I never found my IR thermometer to be all that accurate when pointed at the shiny CA evaporator. |
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Post by cablehack on Dec 11, 2014 0:58:39 GMT
These are my findings as well which is why I switched to DMM and thermalcouples. I never found my IR thermometer to be all that accurate when pointed at the shiny CA evaporator. I would agree. Thermistor frozen the bottom centre of the evap gives a nice stable reading...plus you can monitor the temp with the door shut. I would have gone nuts trying to calibrate the temperature differential of the thermostat had I used my IR thermometer. |
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Post by coldspaces on Dec 11, 2014 3:31:44 GMT
I never did switch from the bead probe thermometer to the IR. Heard so many story's about what made them inaccurate. Even back when I started in 1977 my grandfather owned and used a Thermal brand electronic thermometer. Wasn't any small bead probe on it but at least it was accurate and could be used without opening the door to look.
My grandfather knew to never trust the customers thermometers. In his early days he was called to a locale store to check the meat cooler. It was his first time he had been called to that store. He checked the case using his thermometer with the scale printed into the glass and set the control. 45 minutes after arriving he told the butcher it should be ok now and he refused to believe him. Said there was no way he could have fixed it that quick. They had spent about $1500(late 60's money) on the cooler with other company's who could not get it set to a constant temperature.
Well that's a little hard to do when the thermostat was some cheap free give away item and the glass tube was lose and could freely move in relation to the scale printed on the metal back. Grandfather said it read a different temp every time you picked it up. They called him for years after that one.
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Post by blackhorse on Dec 11, 2014 4:22:38 GMT
Exactly.
The Fluke rep's demonstration at the trade show pointing the IR into his glass of soda and reading 28F convinced me it would never be any use reading return line temp. (You know damn well the soda wasn't 28F; I'd guessed it at about 40.) I got a cheap/decent one a while back because they are a good way to find hot electrical connections and fuses/breakers without touching live components, if you don't feel like springing for $1200 for a FLIR imaging outfit. But useless for refrigeration work. I have some 2-wire thermistor digitals with magnets on the back and long wires that close in the doors, and record max/min/current temps. I also have an old-school recording one that prints out a tape for the customer's records if they want.
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Post by jhigdon2 on Dec 11, 2014 4:46:26 GMT
You got a good point there. Even though I have a decent raytec thermometer there still can be alot of fudge factor especially on shiny surfaces.
I ran the unit again for an extended period of time and overall I'm pleased with its performance. It settles down to about 135 watts. It's quiet and cold. (About 6 deg). After about 20 minutes of constant running, the frost line on the rt side drops to just below the tank. Upon shut off, I notice more than usual bubbling sounds coming from the oil sump. So I have to assume that either the cap tube still needs to be shortened slightly, or it needs a little bigger oil heater. Either way, I think it's gonna work just fine. Next thing to do is put it on a box and do long term real world test. I'm really curious if issues will arise with oil migration. I like R123. It's pretty similar to MF, but has a little more performance on low temp. The run amps are really low and it seems like the compressor is quieter than MF.
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Post by blackhorse on Dec 11, 2014 5:11:51 GMT
Are you quite sure the bubbling is in the oil sump, and not in the evaporator?
Recall that a properly sized capillary passes some refrigerant gas for some time after shut-off, until pressure equalizes, which would bubble into the liquid in the evaporator (unlike with the float valve, that never passes gas).
I'd hate for you to worry if you don't need to; it seems to be going so well.
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Post by jhigdon2 on Dec 11, 2014 5:28:47 GMT
Pretty sure oil heater is boiling some excess refrigerant out of the oil. It's got that trademark bloop bloop sound. It's virtually the same sound that MF makes when there is a surplus in sump. But then again I was running it pretty hard. R123 has a little higher boiling point than MF, so I was kinda wondering if some of it would gather in the sump if there isn't enough heat to keep it chased out.
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Post by cablehack on Dec 11, 2014 5:34:09 GMT
A rattle free CA in the making perhaps? The lower current draw would suggest it's not going to rattle when it's working hard, so it will be interesting to see if it has the same refrigerant condensing in the dome problem (and thus rattling) on a cold winter morning.
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Post by ChrisJ on Dec 11, 2014 13:41:57 GMT
John asked me to post these pictures. What I'm wondering is, if we find the CA can run on this stuff, how can us smaller guys get some? Attachments:
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Post by blackhorse on Dec 11, 2014 13:45:46 GMT
A rattle free CA in the making perhaps? The lower current draw would suggest it's not going to rattle when it's working hard, so it will be interesting to see if it has the same refrigerant condensing in the dome problem (and thus rattling) on a cold winter morning. I'm not familiar with the rattle, not having one of those machines, but refrigerant condensing in the housing at low ambient problems are characteristic of pretty much all the high side shell compressors, old or modern. |
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