Troubleshooting guide
Dometic Single Zone LCD hot-weather filter maintenance
Dometic Single Zone LCD thermostat instructions say High Fan/Cooling gives optimum efficiency in high humidity or high outside temperatures, heat gain should be reduced with shade and closed doors/windows, and the return-air filter should be washed at a minimum of every 2 weeks of operation.
Use this atlas to identify likely meaning and prepare for service. Shut off power, LP gas, fuel, or water when a listed appliance condition involves flame, gas smell, exhaust, generator shutdown, high temperature, moving jacks/slides, refrigerant, 120 VAC, control boards, repeated ignition failure, or a persistent lockout. Call the appliance maker, RV dealer, or a qualified RV technician for repair.
Owner-safe checklist
- Use normal HIGH FAN and COOL controls during high humidity or high outside temperature.
- Park in shade when possible, use window coverings, keep doors and windows closed, and avoid heat-producing appliances.
- Wash the owner-accessible return-air filter with soap and warm water at least every 2 weeks of operation, let it dry, and reinstall it before running the air conditioner.
- Call qualified RV HVAC service if owner-visible heat-gain and filter checks do not improve cooling.