Originally Posted by andysherard
I’ve got a used 2018 27FB that is less than a year old. The batteries lost their charge and needed water in the cells. After adding water I’ve noticed the batteries seem exceptionally warm and are making small hissing sound with a strange odor.
Everyone is right - replace converter and batteries. This happened to us at the KOA in San Diego one weekend. We had the same symptoms: hot, smell, and sound.
Don't do what we did - one for one converter replacement. Being on the road, and being that the local RV parts place had what we needed, we missed the chance to get better. Upgrade your converter to a better one.
Also, recommend AGM batteries.