As long as you have propane and good house batteries you can operate your furnace as in almost all cases the blowers for the furnace run off of 12 volt DC being provided by your house batteries.
That being said; your house batteries will have to be charged in order to keep operating the furnace on a daily basis. So you will either have to plug the RV in or run the generator to charge the house batteries.
If you have not used your RV Furnace in a while it might be a good time to make sure that is ready to operate. You might want to take a look at the video below by the RV Professor to learn what you need to do get your furnace ready.
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