Tried using a thermal imager on a fridge compressor that was barely running warm

Had a fridge call last week where the compressor felt only slightly warm to the touch. Usually that means it's shot or the run cap is bad. I busted out my FLIR meter just to see what was up. The compressor showed 95 degrees on the discharge line. That's way too low for a working fridge. I checked the cap and it tested fine at 10 uF. The start relay was clicking on and off every 30 seconds though. I pulled the PTC relay and found it was cracked inside. Swapped in a new relay and the compressor kicked on hard. The discharge line climbed to 145 degrees like it should. Now I always check thermal readings before I condemn a compressor. Anyone else find weird relay failures that mimic a bad compressor?

3 comments

3 Comments

faith_king24d ago

Funny how a tiny cracked part can fake a big failure.

lee_reed23d ago

Wait, hold up. A tiny crack can "fake" a big failure? That sounds kinda wild but I'm actually shook by how right you might be. Like, you're saying that small flaw might not even be the real cause but just looks like it is? There's this thing with old car engines where a hairline crack in the cylinder head gets blamed for overheating, but really the whole cooling system was shot for years. The crack just showed up at the end and took all the heat. Same with those space shuttle o-ring failures everyone talks about - maybe the real problem was way bigger but that little rubber ring was an easy scapegoat. This makes me rethink all those "small defect = disaster" stories I've heard.

gavinb9724d ago

Gotta disagree a bit here. A tiny crack in a critical part can create a chain reaction that brings down a whole system. Look at airplane wing spars or bridge cables - sometimes a small flaw is all it takes for stress to spread and cause a full failure. That crack might seem tiny, but it can disrupt load paths and lead to disaster. Isn't that more about the engineering behind it than just luck?