Help with the understanding of how they work. I was given a 1997 DYNASTY DYN2000Hot tub. Was told it was working before disconnected. As far as I can tell everything except the heat is working. I ohmed the heater out and it was 12 ohm. I understand that is good for this heater. I just am not getting voltage to it. Where to start. No errors on the control pad. I understand overheat freeze protection pressure all play a part. But there are no errors to indicate any issues there. where next. Thanks