Dometic Thermostat Troubleshooting

The tables below are troubleshooting instruction for fixing different Dometic Thermostat models. If you experience some problems, the device will display some certain error code – you don’t have to search for a paper manual to discover the cause of the problem. It’s already mentioned in the tables below. Identify the problem and fix it with the help of step-by-step instructions – they are quite simple for understanding. However, if you’re not tech-savvy enough, a repairman’s help may be needed to perform the operations mentioned below.

Dometic 3313192 Thermostat Troubleshooting

Error coneSolution
E1Loss of communication between the Single Zone LCD thermostat and the module board. LCD will cycle between E1 and the previous mode setting. System will shut down.
E2Open circuit or out of range Indoor Temperature Sensor. Heating and cooling operation will be locked out. Fan operation can continue to operate.
E3Shorted Indoor Temperature Sensor. Heating and cooling operation will be locked out. Fan operation can continue to operate.
E4Open circuit or out of range Outdoor Temperature Sensor (select models). Heat Pump operation will be locked out. Air Conditioner, Fan and Furnace operation can continue to operate.
E5Open circuit or out of range Freeze Sensor. Air conditioner mode of operation will be locked out. Furnace, heat strip, heat pump and fan mode of operation can continue to operate but displays the last temperature set-point.

Dometic 3312026 Thermostat Troubleshooting

Error codeSolution
E1Loss of communication between the CCC 2 thermostat and all system power module boards. System will shut down.
E1Loss of communication between the CCC 2 thermostat and an individual system power module board. The LED will display error code El and the zone number that lost communication. Any additional zones that loose communication will blink in addition to the current zone.
E2Open circuit or out-of-range indoor temperature sensor. All heat, cool, and dehumidify operations will be locked out. Manual fan operation will continue.
E3Shorted Indoor Temperature Sensor. All heat, cool, and dehumidify operation will be locked out. Manual fan operation will continue.
E4Open circuit or out of range Outdoor Temperature Sensor (select models). Heat pump and dehumidification operation will be locked out. Air conditioner, furnace, heat strip and fan operation can continue to operate.
E5Open circuit or out of range Freeze Sensor. Air conditioner and dehumidification operation will be locked out. Heat pump, furnace, heat strip and fan operation can continue to operate but displays the last temperature set-point.
E6Open circuit Humidity Sensor (Select Models). Air conditioner and dehumidification will be locked out. Heat pump, furnace heat strip and fan can continue to operate.
E7Loss of 120 VAC power to all power module boards on the system. The system will shut down.
E8Invalid zone configuration. The heat pump and heat strip DIP switches are both set to the ON position in one zone. Heat pump, heat strip, air conditioner, and dehumidify operation will be locked out in the affected zone.
E9Invalid zone configuration. The dehumidifier DIP switch and either the heat pump or heat strip DIP switches are set to the ON position in one zone. Heat pump, heat strip, air conditioner, and dehumidify operation will be locked out in the affected zone.