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DD716TED's avatar
DD716TED
Explorer
Oct 09, 2021

Battery Issue?

We are camping and I noticed something that I had never noticed in the 11 years we have owned the trailer.. We are plugged into pedestal power. When nothing that requires 12 volts is on, the 12v power monitor meter reads 13.7 volts dc.. However when the refrigerator is on (not on gas), the dc power drops to 12.6 vdc AND when the furnace cycles on with refrigerator on, lights dim and 12 v power monitor meter drops to 11.7 volts dc.. Don't ever remember seeing this in the past..ARE MY BATTERYS FAILING? Help please.. easier to find new batteries on Saturday than Sunday when camping..
  • DD716TED wrote:
    when pedestal power is disconnected, fridge still works and furnace still runs.. but for how long?? didn't want to find out..


    To be sure they will not get so low that you can't run 12v things, you need to recharge the batts. They are low now, so you could get a simple auto battery charger today and leave it clamped on the batts since you have 120v to run it.

    If you got new batts today, they will just get run down too with no battery charging. You could get new batts and a battery charger. Depends how old the batts are in there now.

    You need a working battery for the trailer when it is on the road in case of a breakaway.

    I am confused about the 12v monitor showing that 13.7v and then also showing the lower figures when 12v loads come on.
  • when pedestal power is disconnected, fridge still works and furnace still runs.. but for how long?? didn't want to find out..
  • BFL13 wrote:
    It appears the converter is is working to supply that 13.7 to the monitor somehow, but that the fridge and furnace are on battery.

    Something is blown so the converter's 13.7v is not reaching the fridge and furnace and also note the battery is getting lower with use, as indicated by the voltage drop when the furnace comes on.

    You can keep going that way until the battery bank gets too low and then you will need a battery charger, or else get the converter back on line.

    You don't need new batteries now, just a battery charger.

    BTW the fridge on 120v does use a little 12v for its controls
  • It appears the converter is is working to supply that 13.7 to the monitor somehow, but that the fridge and furnace are on battery.

    Something is blown so the converter's 13.7v is not reaching the fridge and furnace and also note the battery is getting lower with use, as indicated by the voltage drop when the furnace comes on.

    You can keep going that way until the battery bank gets too low and then you will need a battery charger, or else get the converter back on line.

    You don't need new batteries now, just a battery charger.

    BTW the fridge on 120v does use a little 12v for its controls
  • Could be. Have them tested IMO. How old are the batteries? 11 years is a great life for a wet battery.

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