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cmcdar's avatar
cmcdar
Explorer
May 02, 2015

HELP Electrical problem!

Picked up new to me camper Trail Cruiser c191 (Hybrid) travel trailer.

Battery was quite low so put a charger on it, while still connected to the camper. This morning I go out to check the voltage of the battery and it is "boiling".

I had disconnected the power to the the charger so there was no charging overnight. This morning the charger was humming and the battery is 'boiling' (hot, battery acid coming out the top). I disconnected the charger and disconnected the battery from the camper. It was almost as if the power was flowing from the camper to the battery (camper plugged into shore power - regular house extension cord).

When I went inside the camper my fuse panel was humming YIKES. Needless to say, I disconnected the extension cord.

Anybody have any idea what on earth happened?

Thanks so much!
  • Do you think there is any problems caused by this to my fuse panel?
  • Measure the voltage but the battery probably has a shorted cell and should be used as a core when you purchase a replacement.
  • There's no harm in running two chargers in parallel. They will either share whatever current the battery will accept, or one will contribute little to nothing, while the other carries the load. The "boiling" is likely a result of too high a voltage coming out of your on-board converter.

    Power up the converter while disconnected from the battery, and check it's output voltage. Should be in the 13.6v range, or whatever is listed as it's "nominal" output voltage. Then connect it to a slightly depleted battery and observe the voltage. Should be no more than 14.4 - 14.8v (the converter's bulk voltage setting).

    Post the make and model of your equipment... battery, charger, converter-charger for more help.
  • Hi,

    The battery is three years old. Yes, I checked the battery water and all cells were full. This is a 2007 camper but the newest one I've had til now was a 1987 so I was not aware that shore power would charge my battery. HOWEVER, I disconnected the power cord from the battery charger and used it for my "shore power". IF the battery was bad, do you think that might have caused the problem?

    The battery did have enough charge to power my 12v lights but not enough to power my new LED replacement bulbs.

    Thanks for any incite.
  • cmcdar wrote:
    Battery was quite low so put a charger on it, while still connected to the camper. This morning I go out to check the voltage of the battery and it is "boiling".

    I had disconnected the power to the the charger so there was no charging overnight. This morning the charger was humming and the battery is 'boiling' (hot, battery acid coming out the top). I disconnected the charger and disconnected the battery from the camper. It was almost as if the power was flowing from the camper to the battery (camper plugged into shore power - regular house extension cord).

    Need a bit of clarification.

    It sounds as if the camper has a converter/charger in it already, but, you said 'battery was quite low'. Do you mean voltage? And if so, was the camper plugged in when you took that reading? Power is supposed to flow to the battery if there's an on-board charger.

    Did you check the battery water? How old is this battery? I imagine very few used trailers have a) a good battery b) good tires.

    One or both of your chargers is a stupid one, and was overcharging.
  • Plugged in to shore power means converter was running and charging the battery. Adding another battery charger to this is only going to cause the battery to be overcharged. That sounds like what happened. Make sure your converter has a multi-stage charge capability. This allows it to charge the battery and then it backs off and maintains the battery. Adding a second charger is not the thing to do.

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