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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