I have a really old portable hottub, so old it doesn't have a heating element...something called a heat blanket on the motor. But it was working until I moved it recently. After checking its control box, I realized a white wire and black wire had become disconnected. Its unfortunate that I didn't know which one went where. Sooo...I tried plugging them one way, then the other. All I get when I hook up the power is a click, no which way the wires are hooked up. Suggestions?