Kenmore Elite Fridge 795.71053.012 white flakes and resistance check

[MEBug]

Model Number

795.71053.012

Brand

Sears Kenmore

Age

More than 10 years

My Kenmore fridge isn't cooling down the fresh food compartment and freezer right after 10 years of usage. I followed the technical guidance to check the 3 test modes by pressing the button on the PCB and turned out 3 fans (1 condenser fan and 2 evap fans) are working and there is no blinking LED. In the first test mode, I could feel the light vibration on the compressor by touching it. So I wonder if it is the refrigerant issue. I have not recharge the refrigerant. I found there are white flakes on the bottom tray just under the soldering spots for suction and discharge ports. I also found there are white powder attached on the ports in addition to the copper green corrosion (see first 2 photos). I also checked the IPM output. They are with infinite ohms between each compressor pin and ground. So the compressor insulation is ok. I also checked the ohm between the power pin and common pin and turned out the reading is 10.4 ohm when the room temperature is 63 F (see 3rd photo).

Does anyone know what the white powder on the copper tubes and white flakes are? Are they normal to be seen on the copper tubes? Is the ohm reading 10.4 ohm normal between the power pin and common pin? The technical guidance says it should be between 6 and 8 ohm, but I did use two clamp extensions between the pin and multimeter probe and each clamp extension has 2.3 ohm when itself is measured. The compressor is LG FC75LBNA.

 

[Jake]

That white powder is usually flux from the weld spot at the factory, no worries about that.

Take the back panel off from inside the freezer and take a photo of your evaporator coil, We need to see the frost pattern to determine if its a sealed system problem.

Look at the very bottom photo below where it says NORMAL FROST PATTERN.

 

[MEBug]

Thank you, Jake. I reset the fridge and allowed it to run for more than 24 hours at the manufacturer default temperature, 37 degrees for fresh food compartment and 0 degree for freezer. After the first hour run, I did not find a leaking spot through the soap bubble test at these soldering joints, so you are correct. The white power is something from the tube OD. I took several photos on the evap coil in the freezer (see attached photos) after 24 hours of operation.

There is a chunk of ice attached on one of the two entrance tubes, prior to the elbow section. The evap coil has no frost. The black stuff on the elbow section is a loose noise/vibration damper. The bottom of compressor housing is warm, not hot. It looks like the refrigerant is restricted at the elbow section, so I think it is a sealed system problem from the 4 patterns. Do you have any suggestions for this problem? I saw it has 3 possible causes for the sealed system problem.

 

[Jake]

There is a chunk of ice attached on one of the two entrance tubes, prior to the elbow section. The evap coil has no frost.

Yes per your photos, you have a sealed system problem.

We don't really get into sealed system repair here, there's a lot to it. Compressor/sealed system work is not a repair a normal consumer can do. Doing compressor/sealed system work is very unique craft that you need to be trained in with lots of hands on experience.

Doing sealed system work requires you to have a turbo torch, acetylene for the torch, knowledge of how to use and weld with a turbo torch, also having a vacuum pump, and the proper amount of R-134a to use, changing the Filter Drier as well, solder, flux, silfloss, sandpaper, etc.

You need to be a certified Type 1 40 CFR part 82, subpart F. AHAM-NARDA Refrigerant Tech. to change Compressors or do any sealed system work involving Freon(Refrigerant Gas). I got certified on 11-17-1994 when i worked for Montgomery Ward Service Dept.

You'd have to have a licensed refrigeration tech come out and do it for you.

 

[MEBug]

It sounds the core module is no longer functioning and will need a significant surgery for my 10-year-old fridge. I got your point. Thank you again, Jake.

 

[Jake]

Glad to help.