Bought one of these, analog version, and I can't seem to get it to work. It is hooked up to a decent Frigidaire refrigerator and since it has no power light, makes no noise, and does not seem to turn on the compressor--I am wondering if I bought a dud. The temp rises past where it is set. I don't sit next to it, but I have not heard the unit turn on even once when it is hooked up. I have been turning on the power by unhooking it, since I have 9 gallons of Kolsch in there, and monitoring the temperature myself. I have it hooked up via extension cord, does anyone think this matters?