Can we run the water heater and pump off the battery? May 10, 2024 at 3:22 pm #40941 IA_CamperParticipant Joined: Jan 2024 Posts: 132 Likes: 142LikeUp0::Like Bill said, you will need battery for both, but you’ll want to use propane for the water heater. They use a lot of electricity but run pretty efficiently on propane, making propane ideal for boondocking.