We have suffered an unplugged freezer in our house. It's nasty for those that have never been there. Too much lost tuna, deer and such... I do not EVER want to go there again. I need an inexpensive alarm that will inform us when the freezer is too warm. I have searched google.. I guess that I used the wrong keywords. Anyone have any experience with an older freezer and an add-on system? Advice please! HEEEEELLLLLLLP! Thanks in advance!