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ironman_camper's avatar
Aug 28, 2016

battery issue/ 3 way fridge

Newbie here- Have a "new to me" pop up in relatively good condition. By accident, I may have started the 3 way fridge on propane while the DC was on. This may have occurred for a few minutes before I turned everything off and started over on gas. It might not have happened at all. The Fridge ran fine on gas for two days and kept everything cold. However, the DC power in the camper went out within an hour. After a drive home today of an hour and ten minutes, the battery was only charged enough for the CO detector to read "low voltage". Nothing else would work. Don't know if the situation with the fridge might be the cause, or if the used battery is just no good, or something worse. Your help is appreciated!

14 Replies

  • Thanks everyone... The round connector to the vehicle was installed by a reputable trailer dealer so shouldn't the charge line be there? Can I tell by looking under the car or at the plug? I thought for sure 70 minutes of driving would recharge the battery. I thought the idea was to charge the battery while driving to the destination and no other charging was needed.
  • Almot's avatar
    Almot
    Explorer III
    ironman_camper wrote:
    By accident, I may have started the 3 way fridge on propane while the DC was on. This may have occurred for a few minutes before I turned everything off

    Have you started it in propane mode or in DC mode?

    In DC mode it will draw 30A (or more) and will deplete the battery quickly, though not in a few minutes. Could be dying battery.

    Driving for one hour will get you a zilch because the 7-pin plug from truck to trailer provides mere 10A current. You would have to drive several hours to see any results. Put it on a shore charger.
  • The "dc" option as far as I know was really intended for motorhomes to use while traveling and being supplied by the alternator. As you discovered, the battery in a trailer won't last long and the umbilical won't really "top" off a battery in a trailer. Your best bet is to drop a hundred bucks on a new battery, switch to LED lights and stay away from the DC position. You can shut it down for short trips without the food spoiling. Not sure if you can run the fridge on propane while the trailer is folded up, but someone else on here can advise about that I'm sure.
  • ironman_camper wrote:
    Don't know if the situation with the fridge might be the cause, or if the used battery is just no good, or something worse. Your help is appreciated!


    Do you know for a fact that you have an active charge line wired back to the trailer from the tow vehicle? Your fridge, when running on 12 vdc, draws a lot of power and will deplete even a well charged battery quite quickly.

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