Dometic DF furnace blower runs but will not light
Dometic DF operating instructions say a furnace that will not light while the blower turns on can be caused by air in the LPG line or thermostat settings that are not on Heat or not high enough.
Owner-safe checklist
- If there is any gas odor, stop and follow the manual gas-odor shutoff steps before further operation.
- Confirm the thermostat is set to Heat and above room temperature.
- Turn the thermostat off for 10 seconds and back on once; stop if lockout returns.
- If the blower runs but heat still does not start, shut the furnace off and call qualified RV furnace service.