jc
5 Cubic Foot
Posts: 65
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Post by jc on Jul 9, 2021 21:30:29 GMT
Hello all. I got a CA awhile back and finally got around to rewiring it and putting new insulation, new heater and foam gaskets, etc. I plugged it in and let the heater run for a full day, pulling a steady 16 watts. After that I turned on the fridge and it fired up and immediately began cooling. It was initially pulling about 220 watts and after being on for a half hour or so it dropped down to 160-180 range. I purged NCGs and it took 4 bleeds of 3 minutes with the 1 minute interval in between before I saw the oil slightly draw in so I stopped there. Anyway I noticed that it never cycled off. I have had it running for a full 24 hrs now and it has never cycled off. I have the temperature control set on 5 and here are the pictures of the inside. I currently have it turned off but still plugged in so the heater is still running. While the compressor was running it got up to 109 F with my laser temp reader. After it had cooled the cabinet down the compressor temp eventually dropped to around 95-100 F. So my question is, what’s wrong here? My frost line is too high and the darn thing won’t cycle off. Ambient room temp in my garage is 75 F. Thanks all. drive.google.com/file/d/1AlTjXHFmIJIwAObjrm3ZLAZztWDr3Ind/view?usp=drivesdkdrive.google.com/file/d/1hYX0aGUKMrrwUQFo3Du0L0aTyvI0Rc0f/view?usp=drivesdkdrive.google.com/file/d/1ozXzx_5Hzj6ZI38sEdTFEJyoTgtIIDif/view?usp=drivesdk |
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Post by turbokinetic on Jul 9, 2021 23:43:42 GMT
Hi, your photo links are not working.
Based on the description, it sounds like one of two things are happening. Either the control is not cycling off, and is allowing the compressor to run all the time even though it's too cold already - or the float metering valve is not working correctly and is allowing too much flow of refrigerant through the system. If the float valve is not working properly, the unit will need internal repairs.
Do you have a thermometer? Can you place this in the lower part of the evaporator and see how cold it gets after running for several hours?
Sincerely,
David
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jc
5 Cubic Foot
Posts: 65
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Post by jc on Jul 10, 2021 0:58:37 GMT
David,
Thanks for the reply. I reattached the picture links. Hopefully they work this time.
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Post by turbokinetic on Jul 10, 2021 1:16:21 GMT
David, Thanks for the reply. I reattached the picture links. Hopefully they work this time. It says access denied. |
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Post by cablehack on Jul 10, 2021 1:22:33 GMT
Unfortunately the links don't work for me either. It seems to be an access problem.
First thing to know, is what is the temperature of the evaporator? Measure this at the bottom centre of the evaporator. If it is not low enough the thermostat will never shut off. The temperature should get to less than 10 degrees F (the actual temperature ranges are listed in the manual). If it can't, the usual cause for this is a worn float valve - not uncommon for CA units. If the evaporator temperature is low enough and it's still not shutting off, then the thermostat is the next thing to check.
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jc
5 Cubic Foot
Posts: 65
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Post by jc on Jul 10, 2021 1:23:44 GMT
3rd time is the charm. I changed access to the links. They should hopefully work now.
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Post by cablehack on Jul 10, 2021 1:31:50 GMT
All ok with the links now. It's certainly not short of methyl formate, and the float valve is not blocked, so that's a start. And it looks to be free of NCG's.
My suspicion is the temperature is not low enough. You'll need to measure the evaporator surface directly with a thermometer bulb frozen to it, or a laser thermometer pointed at it. The fridge thermometer in your pic only shows the air temp around it, not the actual evaporator temperature.
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Post by ChrisJ on Jul 10, 2021 11:34:41 GMT
When running is the evaporator loud, like a water fall flowing through it (violent boiling), or is it fairly quiet with a tight crackling sound?
I find it interesting the equalizer and suction line are fully frosted but the float valve liquid line is bare.
The frost also looks very fluffy, perhaps running warm due to bad float valve?
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jc
5 Cubic Foot
Posts: 65
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Post by jc on Jul 10, 2021 12:08:31 GMT
Chris, I would say overall the entire machine is quiet, no rattling like in videos I have watched about CAs needing bled.
As for the evaporator I can hear some crackling/waterfall sounds but I wouldn’t call it super loud.
Cablehack…. I have to go to town today and run some errands, I will try to find a thermometer that will lay flat against the bottom of the evaporator so I can get an accurate reading. I’ll also double check the temp with my laser gun.
From being completely off (except for the heater) how long should it take to cool down to around 5-10F before I start checking those temps?
Lastly, if it is in fact a worn float valve or bad temp control. Is there anyone out there who can repair these?? I do not have the skill to even attempt the float valve- capillary conversion. As for the temp control it seems very delicate and since these are so scarce I would feel more comfortable with someone experienced giving it a try.
Thanks
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Post by ChrisJ on Jul 10, 2021 13:53:17 GMT
Jc, With a bad float valve the evaporators seem to boil very different from when running correctly. The overall machine could still run very quiet. This is what it should sound like after running for 15-20 minutes. A very tight crackling sound rather than bubbling and boiling. youtu.be/l1XmCE_qR7E |
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Post by turbokinetic on Jul 10, 2021 15:07:04 GMT
Chris, I would say overall the entire machine is quiet, no rattling like in videos I have watched about CAs needing bled. As for the evaporator I can hear some crackling/waterfall sounds but I wouldn’t call it super loud. Cablehack…. I have to go to town today and run some errands, I will try to find a thermometer that will lay flat against the bottom of the evaporator so I can get an accurate reading. I’ll also double check the temp with my laser gun. From being completely off (except for the heater) how long should it take to cool down to around 5-10F before I start checking those temps? Lastly, if it is in fact a worn float valve or bad temp control. Is there anyone out there who can repair these?? I do not have the skill to even attempt the float valve- capillary conversion. As for the temp control it seems very delicate and since these are so scarce I would feel more comfortable with someone experienced giving it a try. Thanks Hi JC. Pictures are working now! The thermometer you have is an air temperature measurement device. It won't register the actual temperature of the evaporator. You'll need a thermometer with an exposed metal probe which will become embedded in the ice on the bottom of the evaporator. If the unit isn't reaching cutoff temperature, there is likely a problem with the float valve seat. If the needle valve doesn't close all the way, it will continue to admit hot vapor form the high pressure side after all the liquid has passed into the evaporator. This hot vapor will present a constant source of pressure in the low-side. This prevents the compressor from pulling the proper vacuum and therefore reaching the lowest temperature it is designed to reach. The vapor percolating through the evaporator will make noise and will cause a high frost line (at first) by pushing liquid further through the system than it would otherwise go. If the float valve is bypassing, it is possible to repair in one of two ways. The way I prefer because to me it is less invasive and keeps the unit original - is to re-cut the float needle seat. That way you retain the original operating characteristics of the system. Another way is to replace the float valve with a capillary tube. Either way will restore the unit to operation. If it is reaching the proper temperature but the control isn't cycling off; then the control is not working correctly. That can also be repaired. Normally all those need is cleaning and lubricating the internal parts. There are a few of us who do this type of work. I do repair these, on a limited bases, as a hobby. You would have to bring it to my place in Northport, Alabama. Sincerely, David |
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Post by cablehack on Jul 11, 2021 0:26:00 GMT
The frost also looks very fluffy, perhaps running warm due to bad float valve? That's what I thought too. Even though there's plenty of frost, it doesn't look right. |
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jc
5 Cubic Foot
Posts: 65
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Post by jc on Jul 12, 2021 13:03:05 GMT
Hi all, I couldn't find a suitable thermometer so the one I ordered should be arriving today. I will place it in the bottom center of the evaporator and turn it on tonight. I will also try and take a short video so you can here the sounds it is making. After watching the Youtube video posted by ChrisJ though, I believe my fridge is louder at the evaporator, but I can't be sure. At any rate I will get an accurate temperature and go from there. As for the frost, for the first few hours the frost looked healthy and normal. After running for an entire day nonstop if when it got that fluffy appearance. I will attach a picture to this message that shows the frost after 45 minutes or so of it running. (this thing also has a door gasket that has gaps) I have bought some weather stripping and will try and add that tonight before my test run to eliminate that variable. David, as for repairs, I will send you a message shortly to discuss options. I appreciate everyone's help so far. Here is the frost line after about 45 min to 1 hour of operation. drive.google.com/file/d/1ekrb4la8UgDIdSiuAuFxNbhyR4-9JSIn/view?usp=drivesdk |
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Post by ckfan on Jul 12, 2021 23:14:41 GMT
Honestly that frost line looks normal to me. Hmm, strange.
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Post by cablehack on Jul 13, 2021 0:34:57 GMT
The crystaline pattern in the ice has me suspicious. I could be wrong of course, so will be interesting to see what the actual temperature is. This is how the first frost should look:
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