Hi, I'm new to this forum. I posted this on an old thread: https://forum.allaboutcircuits.com/...t-,Danfoss Compressor Speed Controller,-Reply, but have had no reaction.
My Waeco, with Danfoss BD50F compressor, got sea water in the electronics, and the 220v packed up. I took all electronics out and connected straight to 12v with a standard mechanical freezer thermostat. It worked well, but the thermostat started playing up so installed an electronic thermostat to it, not realizing that it fed 12v into the thermostat circuit C & T. It has now stopped working, even if I bridge C&T.
Where do I start looking?
Is there an easy answer? or bypass? I am not an electronic fundi, and it's too expensive to replace the controller on an 18 year old fridge?
Would appreciate any help on this

 

...it fed 12v into the thermostat circuit C & T. It has now stopped working, even if I bridge C&T.
Where do I start looking?

Applying 12V there likely roasted something. Check the resistors in the C-T circuit, first visually and then with a multimeter if a burnt component isn't obvious. From the other thread it looks like there may also be transistors in that circuit that could be vulnerable. See if you can find those.

 

https://forum.allaboutcircuits.com/...t-,Danfoss Compressor Speed Controller,-Reply Just posted here.