LFX31925ST LG Refrigerator stopped working suddenly

[niceguy]

Model Number

LFX31925ST

Brand

LG

Age

6-10 years

Hello Guys,

My LG refrigerator LFX31925ST has stopped working suddenly. No cooling in the refrigerator or freezer. No error codes.

I removed the back panel and thoroughly cleaned the compressor and condenser coils. Condenser fan is working. Compressor also seems to work - humming and warm to touch (not very hot).

What should I look for as possible causes. Are there any diagnostic tests I can run? I am fairly handy and DIY with EE background. And have several years of experience building electronic circuits at home and as a profession so not afraid of checking the main control board.

Please guide me.

Thanks.

NG

 

[Jake]

Hi NG,

If the compressor is running and there is no cooling at all then the sealed system is the problem.

The sealed system consists of the compressor, condenser, evaporator, heat exchanger, filter/drier and refrigerant. Common problems with a sealed system are bad compressors, refrigerant leaks, and system restrictions.

You can check your owners manual warranty, some models have up to a 10 yr. warranty on the compressor, and on LG models the compressors are fairly common to go bad when it completely stops cooling.

Jake

 

[niceguy]

Hi NG,

If the compressor is running and there is no cooling at all then the sealed system is the problem.

The sealed system consists of the compressor, condenser, evaporator, heat exchanger, filter/drier and refrigerant. Common problems with a sealed system are bad compressors, refrigerant leaks, and system restrictions.

You can check your owners manual warranty, some models have up to a 10 yr. warranty on the compressor, and on LG models the compressors are fairly common to go bad when it completely stops cooling.

Jake

Hello Jake,

Thanks a lot for the info. Also, I found a couple of service manuals you had posted earlier on this group. What a great contribution. I have downloaded the manuals and also tried a few more tests.

Here is my day's worth of data points -

1. Under normal operating conditions (ICE PLUS mode OFF) the compressor seems to be running but no cooling. There are no error codes and the error LED on the main control board shows no error blinks.

2. I turned the ICE PLUS mode ON. After some time noticed increased compressor noise that eventually gave a sudden scratching sound and the compressor stops after that sound. It remains stopped for quite some time. I also noticed the LED on the main board is blinking error code 6. That according to the service manual is "circuit overcurrent error".

These observations make me believe that the compressor is probably bad which when operated under heavier duty (ICE PLUS mode) is causing over current.

Also, on the side I called LG and they did confirm that the compressor will be replaced free as it is still under warranty. But they said only the cost of compressor is covered not the labor.

Just 2 months ago in July I fixed my car AC by replacing the compressor, condenser and expansion valve. So I am familiar in dealing with R134a refrigerant systems. I have access to vacuum pump, AC manifold gauges. Do you think replacing the compressor on the refrigerator a DIY job? The only thing I notice different here is it involves soldering/brazing vs. bolted fittings.

What do you say?

Thanks again for being such a great mentor & helper.

- NG

 

[Jake]

They won't send you a compressor for free for you to do it yourself, only way to get a free compressor is having the tech. install it.

Jake

 

[niceguy]

They won't send you a compressor for free for you to do it yourself, only way to get a free compressor is having the tech. install it.

Jake

Thanks got it.

Luckily I found a local guy who is capable of replacing compressors. Does he have to be a LG certified tech or someone approved by LG?

Separately, I notice on AppliancePartsPros.com that a new compressor replacement requires associated "Sw Rewriter Assembly". What is this? Is it like an electronic module to be added for SW update? Is this is something the tech would know?
(I work in embedded system hardware electronics for my day job so very familiar with SW upgrades hence asking details).

Thanks a million again,

NG

 

[Jake]

Yes, it has to be a LG authorized tech that has to replace it.

a new compressor replacement requires associated "Sw Rewriter Assembly". What is this? Is it like an electronic module to be added for SW update? Is this is something the tech would know?

I really don't know since I'm not a LG authorized tech. But I remember someone posted something about that here as well.

I just found it. It was Rick! LOL

Look here:

795.74053410 Kenmore Elite Refrigerator (LG) Working too good?

I couldn't find any reference to updating the board in the LG info I have and I don't see any USB connections on the board. If it has an update on it for the new compressor then replacing it with a new board, it won't have the update. I'll check and see if I can find a tech sheet and wire...

www.applianceblog.com

Jake

 

[niceguy]

@Jake : Can not thank you enough for all your help.

Now I am in a fix because I called LG. I was able to find a way to their diagnostic team and insisted on running the remote diagnostic which confirmed my hunch. It is a bad compressor and only authorized tech can order it. The problem is finding a LG technician. They provided a list but some of them have very bad reviews and those who have good reviews say they have stopped taking LG refrigerator calls

Any chance you know anyone who you could recommend in the bay area, California?

- NG

 

[Jake]

No sorry, I don't know of anyone in the bay area that is a authorized LG tech.

Jake

 

[niceguy]

Hi,

Turns out I might attempt changing the compressor myself. No LG technician ready to service it and new refrigerators may not be available till December due to COVID :-(

But I am worried - what if there is a restriction somewhere in the system?

One question - Is it a good idea to use the AC system flush (like you use in Auto AC) using the chemical and compressed air? Or given such a small cross section of Cap tube, is it better to reverse flush. I am thinking of using similar chemical but in reverse direction from the suction line driven out thru the cap tube after cutting out the filter-drier.

And then I guess I will have to flush the condenser separately.

What are your thoughts?

Note this system has a 3 way valve due to separate cooling circuits for freezer and refrigerator.

Again thanks for all your help and guidance.

- NG

 

[Jake]

Sorry NG, we don't teach sealed system repair here, way too much involved in doing these repairs.

Jake

 

[Jake]

Lowes has plenty of refrigerators in-stock in YOUR area:

https://www.lowes.com/pl/Refrigerators-Appliances/4294857973?goToProdList=True&searchTerm=refrigerators&inStock=1&rollUpVariants=0

Jake

 

[niceguy]

Hmmmm OK the link doesn't work but will check it out tomorrow in the store. Thanks ....

 

[niceguy]

Sorry NG, we don't teach sealed system repair here, way too much involved in doing these repairs.

Jake

@Jake : Understood. Just was going to use this opportunity to learn more about refrigeration systems. Do you mind answering a few questions along if I experiment with the refrigerator which is going to the graveyard anyways.

Thanks a bunch.

NG

 

[Jake]

Hmmmm OK the link doesn't work but will check it out tomorrow in the store. Thanks ....

It works great for me, it says Dublin Lowes IN-STOCK Refrigerators, turn your ad block off or use a different browser.

Do you mind answering a few questions along if I experiment with the refrigerator which is going to the graveyard anyways.

I wish I could, but I'm swamped with field service calls in addition to answering questions here.

Trust me, you need lots of hands on training before you start doing sealed system work.

Jake