Converter Charging Rate 15.5

[Jeepjunk4]

I just replaced 1 of the batteries in my as 2 weeks ago. The po had 2 mismatched batteries in it. I checked them both when I got home and found 1 had a charge of 6.6 volts after being plugged in for a week and the other, good one was at 13, but there seemed to be a lot of wetness around it, attributed it to the po having overfilled it. Put the new battery in it and left it alone.

Today I was doing some painting on the tongue and happened to brush the battery door and it was warm. I opened it up and the battery was hot, the old battery that I didn't replace. The new battery was cold, so I took them both out. Testing with a multimeter, the old battery showed 10.6 volts and the new showed 14.8. I tested the cables and they were both showing output from the charger at 15.5, too high me thinks.

So is the converter shot, I don't know.

[daveswenson]

Sounds to me like the old battery is bad. 15.5v is recommended equalization charge. I'd get a new battery in there before your good one is destroyed.

[idroba]

Old and new batteries virtually never mix well. Sounds like the second old battery just died with a short, that is why it was hot.

The original converter/charger in your rig is due for a replacement, even if it was new. You need a good 3 stage charger such as a Progressive Dynamics PD 9245 which will deliver the proper charge currents to the batteries.

Open circuit voltage on your old Univolt converter/charger is not a very reliable indicator of the charging reality, but it should be replaced in any event.