LG Refrigerator LDN22735 - compressor starter relay questions

[Telkwa]

Model Number

LDN22735ST

Brand

LG

Age

More than 10 years

Trying to figure out what's broken.

The LG is not keeping things cold. It's out on the porch now, not in service.

I've been googling for ideas to test the compressor.

Checked for continuity between the 3 compressor pins. Got something with every combination of pin. So that's good, right?

Then I checked each pin to the outer shell of the compressor. Basically, checking pin to ground. I got continuity with every pin. That's bad, right?

On our LG, the start relay only attaches to two of the three compressor pins. Attached to the third pin (the lowest of the three) is a small electronic gizmo of some kind. It's got a white nylon body, and a black wire coming off of it. I don't know what this thing does.

My wife and I ran this test a few times to make sure. We plugged the fridge in. The circuit board makes a soft "tick" and the fan that blows across the coils spins up. About 30 seconds later that little white plate attached to the lowest pin on the compressor makes a distinct "tick" noise. Sometimes we thought we saw a little spark or arc at the white plate.

I've dug into some of these appliance websites but can't find any mention of the white plate attached to the third pin.

I'll try to attach a pic.

 

[Telkwa]

Did some googling - it looks like the little plate-like device is an overload protector. That's what it looks like to me anyway. Confirmation would be great!

Let's assume I measured the three pins to ground correctly. All three pins showed continuity to the compressor shell. And the overload keeps popping every few minutes. Would that lead a person to think the compressor is shorted out?

 

[paulhl]

You just answered your own question if you tested correctly

 

[Telkwa]

Yeah, it's just that I don't have confidence. If I'd tested a few hundred dead compressors, and had someone to bounce questions off of, it'd be different.

I'm on my own with just the internet, you guys, and my multimeter.

 

[paulhl]

If you have continuity from any compressor terminal to ground it's history, simple.

 

[Telkwa]

OK thanks -
I'll test again just to make sure.

What kinda threw me off was I got continuity pin-to-pin. I didn't write down the exact values. Just wanted to see some good news.

Then I got continuity to the compressor shell from all 3 pins. Not just one or two.

I didn't know if that was unlikely or even possible. Inexperience.

For an example of inexperience, when we first pulled the unit out and started poking around, the compressor was warm. Not super hot, just warm. I was told by a local appliance person that the compressor was working if it was warm.

At that time I didn't understand what was underneath the little black box on the side of the compressor. Now I have a basic understanding of the start/run relay and the overload device. If the overload was kicking out every time the logic sent a "Start" signal to the compressor, what exactly is going on to make the compressor warm?

I appreciate your help!