What's inside an LG Linear compressor. How it moves, why it failed at only 1 1/2 years old.
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What's inside an LG Linear compressor. How it moves, why it failed at only 1 1/2 years old.
I had a Samsung fdbm refrigerator where the week before christmas I got a no cool complaint. Checking the part, it had to be shipped in. It arrived that Friday, and of course it was the wrong evap cover. I devised a plan, but thankfully didn't have to use it. In the end I was able to swap the fan motors and use the existing evap cover but just for fun I garaged a proof of concept using a simple voltage divider circuit.
What it does is take the I put to the fan, and divides it into a lower voltage to tap into and feed back. The output voltage is dependent on the input voltage. It took a bit of playing with to get it right, but it would have worked.
This was the only time I've seen this happen btw.
I had an LG blowing thermal fuses but every time I went out to check it everything tested fine. I was able to finally find the culprit after the 3rd one blew. What was going on was the high limit thermostat was welded shut. Here's the video.
Live demonstration of how resistance in a circuit will affect the current of the circuit.
The tag on the grid represents the wire it is connected to, not the spot it points to when laying down.
Something I didn't mention in the video was that the resistance of the heater is 27.5 ohms.
I've run into a few of these over the years from multiple model numbers and would like to share what I've found with the rest of you guys so hopefully you don't have to learn the hard way. Symptom is that the freezer will not get cold and they may tell you about a hiss even. You get there and put your gauges on it and find it's drawing a suction on the process tube. So after pressure testing the system you find there's a leak in the hot gas loop.
Well here's where it turns into a mess. That hole in the gas line is allowing water to get into the sealed system and you'll never get it out. The only solution is a total sealed system replacement and a really good flush out of the remaining lines using either rx11 or some sort of refrigeration system flush to flush both the condenser and the mullion heater lines to get everything out, followed by nitrogen to flush out the flush.
Here's the last one I ran into, somewhat start to finish along with follow up pictures of the evaporator and compressor cut open to reveal the water that gets sucked into the system and what the water will do to the internals of the compressor. Some are just pictures of brazes. Sometimes I'll take a pic of the backside to look at them, sometimes I think they're pretty, and sometimes I'll just document it to look at 10 years from now. Anyway I left the album raw, meaning if I took a pic that wasn't fuzzy I put it in the album. This job took me 5 1/2 hours to finish and I did it in place not removing the refrigerator from the cabinet.
So I’ve been reading lately and see there is a lot of mis information floating around the web on the use of standard vs high efficiency soaps in modern washers. I’ve seen articles stating that the phosphates are the only thing missing from the soaps and they are fine to use to others saying that the only difference is they are less sudsing and the suds can interfere with the movement of the clothing inside of the washer. Then there’s the absolutely incorrect idea that you can use less regular detergent as well and it will serve the same purpose.
While it is true that they are low sudsing it has more to do with the water tension and the ability of the water to pass through the fabrics to remove the crud. After this crud is removed the detergents job is to suspend said crud in the water to be drained away via the drain pump, in the process not letting them redeposit on the clean clothes. The phosphates have been removed because of algae blooms, nothing to do with the washer. This was more of a problem with dishwasher detergent, not clothes washers. Remember the calls of "My dishwasher doesn't wash as well as it used to" a few years ago?
There is a chemical difference in the soaps being made today. From my less than basic understanding of chemistry I get that soaps are traditionally lye based where detergents are formulated chemicals. High efficiency is made to be able to suspend dirt, dye, oils and all the crap in your dirty clothes in low volumes of water where traditional soaps will not work because they require a high volume of water to work. These new machines are generally using 12 gallons of water where the old types would be around 56. That’s a pretty big difference.
Something that is extremely important in selecting your soap is to be 100% sure that it is real high efficiency soap. I’ve been seeing soaps with the he logo on them that in the fine print say “safe for all machines, including he” and I think this is a downright dirty lye. (See what I did there?) Although it may not be lye based it’s still not real high efficiency and a bearing burner. A recent tour of my local walgreens showed me that an estimated 80% of the detergents there were labeled "safe for all machines".
There are a couple of things that are being observed in the field regarding the use of high efficiency vs conventional soaps.
1. Non high efficiency soap in he machines will cause you problems
2. Using the wrong amount of detergent in he machines will cause you problems
We have all seen multiple problems arise from people using standard soap in their high efficiency washers. This is what I've noticed.
The first and most obvious is how the suds are damaging to the drain pumps. Excessive suds in the drain pump can make it run longer than it needs to run and severely shorten the already short life span that these overpriced Chinese motors are shipped with. The machines can think they still have water in them because the suds interfere with the drain process and can also trigger the water level sensing devises making the pumps run even though the washer has fully drained. This overheats the drain pump and essentially damages it a little every time that happens.
Second are the expedited failures of washer bearings, both on the front load models and on the newer top load agitator-less and fake agitator washers. From experience I’ve seen front loads last for 12 years with moderate use using the correct detergents. I’ve also seen front loads last for 5 years with low use using regular soaps. In the short lived cases they were all using regular soaps or the stuff labeled “safe for all machines including he”. Over the last year I’ve seen multiple top load whirlpool built VMW's and at least one LG with gear cases needing replacement because the bearings have failed. This starts out with a noisy spin and eventually an “out of balance” code. The out of balance will not go away no matter how much redistributing of the load you try to do once it gets bad enough. Some of these were only 2 years old.
Slime, sludge, mold and gookus build up is another issue. Although all of these front load washers are prone to having a mold forming around the tub boot, slime will form on the outside of the inner tub and inside of the outer tub using non high efficiency soap. Using too much soap seems to make it worse. This is what causes the washers to smell like a high school football team locker room. It seems that this problem is getting better with the use of the correct detergents and I personally think the detergents have gotten better since inception but you have to use the correct soap and the correct amount. You can use the clean washer cycle with affresh every week but it’s not doing that good of a job anyway. It’s more of a “way to maintain it” feature than a clean the washer once it gets the buildup.
The point of this is that non he soaps are both causing us to make money (service calls) and not be able to make money on repairs at the same time. When the machines bearings burning up it's a condemnation on the washer most times. The only exception to the rule I've found is the original cabrio washers. I can change the bearing and the suspension and make decent money from the job, but other than that the vmw's and front loaders parts are too expensive to warrant a repair. In the former case the customer could hesitate to call us again for a repair. All it takes is a "her friend said that we went out and charged them to tell them to get a new washer". Although that's completely reasonable it can be a black eye to us and a deterrent for future calls. Prevention to those who will listen can help to preserve our trade and also help to establish it as a value for making their appliances last longer than their neighbors.
From now on potential electrical issues will be a big red flag.
Get into the habit of checking a unit’s frame to a trusted ground before you start working on anything with a power related issue.
I went out on this call expecting something to be wrong with the refrigerator and so as usual I start the standard diagnostic process. It was plugged into a standard outlet and not a gfi so I automatically rule out nuisance trips from being the culprit. I opened the door, felt the hot gas lines, listened to the fans, checked the temps in the freezer and the refrigerator, cycled the icemaker, put the unit into defrost and heard the heaters kick on and start sizzling. Everything seemed to be normal and working as expected.
At this point I figured a mouse may have gotten into a wire or the icemaker line and I really needed to check the back compartment out anyway so I pulled it out to take a look. Again everything looked normal, nothing unusual. I unplugged the unit, checked for continuity between neutral and l1, ground and l1 and again nothing unusual. I plugged the refrigerator back into the outlet and needed to roll it forward a little so I pushed the bare metal back with my hand forward and in doing so my knee hit the copper line coming out of the wall. This is where I simultaneously found the problem and I took 120 volts straight through the chest, violent shaking the whole bit. It hurt like hell and left me scared to touch the damn thing again, but I went back to work.
I checked the outlet and it was wired backwards (hot and neutral reversed) but that's not really that uncommon for a house that's 20+ years old around here. I checked ground to neutral and I got some really big fluctuations in resistance that were sometimes unreadable by my fluke meter so I knew something was going on but not sure exactly what. So I checked ground to the copper pipe. 120 volts. I plugged the refrigerator into a gfi outlet that had a microwave on it and turned off the breaker to the refrigerator and got her in contact with an electrician I know and trust. He went out and a few days later I spoke with the customer again and she told me that the electrician said I was really lucky so I had to call and speak with him about it. I called him and he told me that the ground wire had shorted out to the hot line, energizing everything. I asked him how that was possible without tripping the breaker and he said that the outlet didn't return to ground, that someone had crawled under the house and rigged up the electrical line at some point probably removing the ground and that something chewed the wires shorting the ground and the hot line. The lady said she had no knowledge of it and it must have been done before she bought the house.
I'm making the assumption that something had chewed the wire shorting the rigged up ungrounded ground wire to the hot line. I still don't understand completely what happened but I know I got the shit shocked out of me and if I would have had a hand hold on something I may have been killed, but I wasn't thankfully. It still scares me though. This woman was old and frail and if she would have touched the refrigerator and the sink or the microwave anything to a good ground it probably would have killed her. Be careful with electricity. I've been shocked many times but never like that. 120 volts are extremely powerful. We tend to get complacent with it.