The Control System has detected the power supply polarity is reversed
• Check the 120 VAC wall outlet
supplying power to the water heater for correct polarity and ground using a AC volt meter or a plug in tester.
• Check incoming power supply wiring to the water heater in the junction box - ensure that the hot wire is connected to the water heater’s black wire and the neutral wire is connected to the water heater’s white wire inside the junction box.
• Check for 120 VAC at CCB’s J3 Socket pins 1 & 3 with J3 plug inserted, power on. Check for AC voltage between pin 1 and ground - should indicate 120 VAC. Check for AC voltage between pin 3 and ground - should indicate 0 VAC.
