WFCO converters are almost universally installed in trailers, and almost universally problematic. They can fail in many ways but my most frequent experience on 3 trailers in the family is that they don't go into a period high voltage to equalize the cells. My last one ruined some expensive T105 batteries causing them to boil out eating away a bunch of metal in the front of the fifth wheel. The weirdest one was noisy voltage being put out by the WFCO that caused a Norcold fridge in my son's trailer to malfunction. Replace the WFCO--fixed the fridge--nothing done to the fridge. Do to that experience I wouldn't run a WFCO converter without a battery attached. Suggest replacement with a Progressive Dynamics or BoonDocker converter and a new battery.