Question about using a multimeter vs a test light on fridge compressors

I've been fixing fridges for about 3 years now and always used a test light to check compressor windings. Last week I borrowed a Fluke multimeter from a buddy and tested a dead Whirlpool in Oakland. The multimeter showed me the exact resistance values on the start and run windings, which helped me find a shorted winding that a test light would've missed. Has anyone else switched over to a multimeter for this kind of diagnosis?

3 comments

3 Comments

thomas.parker2mo ago

That multimeter trick is slick but I have yet to see a bad winding a test light missed.

grace5082mo ago

@thomas.parker yeah I used to think that way too until I had a compressor that would trip the breaker after running for 20 minutes. Test light looked fine. Multimeter showed a winding with 4 ohms difference between phases on a 3 phase motor. Put a megger on it and sure enough it had a weak spot that only showed up when it got hot.

mia7482mo ago

Gotta disagree with you there, @grace508 has seen plenty of bad windings a test light missed.