Dometic E3 fault code — Thermostat
Applies to: Comfort Control Center 2, CCC2, 3314080
What E3 means
The Dometic CCC2 operating instructions list E3 as: Shorted indoor temperature sensor; heat and cool operation lock out while manual fan can continue.
Owner-safe checks
- Record the affected zone number and displayed code.
- Turn the affected HVAC equipment off if it is not operating normally.
- Use normal RV power indicators to note whether shore power, generator power, or battery power is present.
Service-only work
- Indoor temperature sensor and thermostat circuit diagnosis should be handled by qualified RV HVAC service.
Safety boundary
Do not bypass thermostat wiring, rooftop equipment controls, module boards, DIP switches, 120 VAC circuits, or freeze/sensor safeties. Shut off the affected HVAC equipment and arrange qualified RV HVAC service for unresolved faults.