JuanMoore said:If it doesn't say STC-1000 on it, it could very well be the similar single stage unit. If so, since you're using it for a keezer, it should work just fine. I have one installed in the collar of my keezer. Let me know if you have questions with the wiring, since it's a little different than the STC-1000.
And I don't know if wiring two controllers in series is such a good idea. There's a lot of issues that could create, and it doesn't really protect against much. A controller dying is much more likely to cut power completely rather than freeze the beer, which a second controller wired in series won't fix. Even if a controller does freeze your beer from a malfunction, it won't really hurt your beer.
I appreciate the advice. I'll think about it as I build the collar. Since the Johnson controller is already on the way with other components I may just return this one to my friend. I don't like the thought of buying and connecting power outlets to it.