TWO refrigerator thermostats which don't break the circuit when they get cold. Is this a common failure mode? appliancerepair

I bought a used fridge recently, and due to other serious problems with it, I removed the thermostat to test it, and then put it back in. After that, the thermostat has been permanently in the "on" position, which would cause the compressor to run without interruption for days if I weren't moderating it with an external thermostat. Turning the thermostat to "0" breaks the circuit and turns the fridge off, but any higher setting than that, even "1", means that the fridge never turns off.

I bought another thermostat on ebay, but it seems to be permanently stuck in the "on" position, too. This makes me wonder whether I made a mistake or have some conceptual misunderstanding about how the thermostat works or needs to be set up... I installed them as described in this video.

I've tested both thermostats by putting them on the "lowest" setting (i.e., the setting which will break the circuit at the highest temperature sticking them in the fridge long enough to cool down to 40 degrees farenheit, then checking whether I get current across the electrodes with a multimeter. I've also tested them by installing them in the fridge with the lowest setting, turning the external thermostat down to 20 degrees, then seeing whether the fridge turns off before it gets into the low 30s.

Assuming I've just had the bad luck of identical failures from both parts, my next step is probably to buy an "official" thermostat replacement.

Submitted October 22, 2014 at 07:27AM by throwaway http://www.reddit.com/r/appliancerepair/comments/2jya93/two_refrigerator_thermostats_which_dont_break_the/ appliancerepair