Evaporator freezes up about once per week. After we manually defrost, all is well for a week or so. I believe it can be one of three parts, but I'm not sure how to test.
1. The defrost thermostat
2. The defrost element (which I can not find the part without the entire evaporator core)
3. The control module.
How can I test these and if it is the defrost element, what is the P/N?

I was able to identify that the defrost (heating) element is bad, but it does not show up anywhere in the parts list. On the GE site, it is number 230, but their part is different than what I have. The part is on the evaporator part picture, but their is no part number (it is the single element one on the left). I need the part, but cant find the P/N and don't need the entire evaporator kit.