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WV_Wanderer's avatar
WV_Wanderer
Explorer
Feb 23, 2015

Expansion tank addition

Will adding an expansion tank to my TT water system cut down on the battery usage while boondocking? I have a 2008 28ft Dutchman Classic and I am considering adding a tank to cut pump usage, thus increase time between charging times. I only turn pump on when we need water for flushing and cooking, of course navy showers.

25 Replies

  • rjxj wrote:
    One way to save battery while boondocking is to not pump water. I have used water straight from a 5 gallon jug instead of putting it in the tank and pumping it.
    Must be fun trying to take a shower!
  • It wont cut down on the amount of time that the pump runs, it will condense the run time. The expansion tank is basically a tank with a balloon in it. When you turn on the faucet the balloon starts pushing water out of your faucet. When the balloon has expanded as much as it can and the pressure switch on the pump falls to the predetermined pressure the pump kicks on. When the faucet is turned off the pump fills the tank compressing the balloon and the pressure builds until the switch shut off pressure is reached.

    Instead of the pump doing short little on and off bursts to keep the lines pressurized, it now has a cushion. Like any other motor, it's best to turn a motor on and let it run and not cycle it on and off. Even with that said, RV pumps do hold up well and last a long time when cycled on and off.

    I installed one along with two GE/Home Depot water filters. At the same time I plumbed the system so that the winterizing port/hose can be put into a 5 gallon water jug and pump into the fresh tank. I dont have to lift any water jugs now.

    One way to save battery while boondocking is to not pump water. I have used water straight from a 5 gallon jug instead of putting it in the tank and pumping it.

    As Smkettner said, LED bulbs make a HUGE difference in amp draw. I would say they are the number one thing to consider for energy savings.
  • No savings. The pump still has to pump a certain number of gallons. The only difference is when it pumps, not the amount.
  • WV Wanderer wrote:
    Will adding an expansion tank to my TT water system cut down on the battery usage while boondocking?
    Not that I'm aware of. Water pumps use very little power. I don't think you'll notice much difference at all.
  • Not going to save much if any battery power with an expansion tank. I still recommend at least a small one though.

    Second battery, better converter, LED lighting, 100+ watts of solar will have a real impact on battery charge level.

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