Troubleshooting guide
Dometic/Atwood water heater lockout light
Use this when a Dometic/Atwood tank water heater fails to ignite, lights the red lockout lamp, or has slow recovery in gas/electric 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
- Turn the water heater mode switch off, then wait before another start attempt.
- Confirm normal LP supply and water-heater mode selection from the RV controls only.
- Stop repeated reset attempts if lockout returns or slow recovery continues.
- Call a qualified RV appliance technician for ignition, thermostat, ECO, or wiring diagnosis.
Official sources
DometicDometic Gas/Electric Combination Function Information | Water Heaters - Combo Gas & Electric | SupportDometicDometic Gas Function | Water Heaters - Gas | SupportDometicDometic WH-6GA/WH-6GEA/WH-9GEA L.P. Gas Water Heater ManualDometicDometic WH-6GA/WH-6GEA/WH-9GEA/WH-10GEA/WH-16GEA L.P. Gas Water Heater Manual