I finally changed how I diagnose fridge compressor issues

I used to always jump straight to checking the start relay and capacitor first on a no cool call. That was my go to move for years, especially on older Whirlpool models. But after a job last spring on a 2019 LG, I spent two hours messing with those parts before realizing the inverter board was the real problem. Now I always hook up my multimeter to the compressor windings before touching anything else. It saves me at least 30 minutes per call and cuts down on returning the wrong parts. When did you guys start focusing on the board over the relay on these new sealed systems?

3 comments

3 Comments

jennifer_jenkins12d ago

Yep, had almost the exact same thing happen on a Samsung a couple years back. Was chasing a hard start kit and relay for an hour before I finally checked the inverter board and saw it was burnt right where the connector goes in. Now I always check winding resistance first thing too. On those newer sealed systems, especially LG and Samsung, I'm pulling out the multimeter before I even touch the relay these days.

craig.mila12d ago

I read somewhere that some techs are now running compressors on a test capacitor first just to see if the windings start pulling high amps before they even check the board. That burnt connector seems like the kind of thing that only shows up after the damage is done though. Why waste time on the relay when the real problem is staring right at you on that board?

val_williams12d ago

Did you notice if the winding resistance readings were out of spec right from the start, or did they only show problems after the board had already burnt? I've seen a few where the windings test fine cold but then act up once they warm up, which makes it tricky to catch without letting it run awhile. Just wondering if that burnt connector was a clear giveaway or if the windings were hiding something too.