Dometic E5 fault code — Thermostat
Applies to: Single Zone LCD thermostat, 3313192, 3313193, 3313194
What E5 means
The Dometic Single Zone LCD thermostat manual lists E5 as an open circuit or out-of-range freeze sensor; air conditioner mode locks out while furnace, heat strip, heat pump, and fan operation can continue, with the display showing the last temperature setpoint.
Owner-safe checks
- Record the E5 code, selected mode, last setpoint, and whether cooling had been running.
- Turn cooling off from normal thermostat controls if the air conditioner is locked out.
- Check only owner-accessible return-air filter condition before calling service.
Service-only work
- Freeze-sensor, evaporator-protection, and air-conditioner diagnosis should be handled by qualified RV HVAC service.
Safety boundary
Do not open thermostat, rooftop HVAC, or electrical compartments, and do not bypass communication or sensor circuits. Shut the affected HVAC system off and arrange qualified RV HVAC service for unresolved Single Zone LCD faults.
Official sources
Related symptom guides
- RV rooftop air conditioner is not cooling enough
- Airflow, venting, or exhaust fault
- Pre-service checklist for RV appliance calls