You need to find out what the model number and brand is for your current converter charger unit.
Also curious how you have determined that the converter is bad. The way to test the converter is to power it up and read the 13.6VDC at the converter/charger DC OUTPUT terminals. It it reads a constant 13.6VDC with Shore Power ON at the DC OUTPUT terminals then the converter/charger is working normal. Since you don't really know where the converter/charger is you must be using some other method to determine the unit is bad. There are three or four reasons why you may not be charging your batteries when on Shore Power with one being a failed converter/charger unit. Blown fuses, blown REVERSE POLARITY FUSES, loose connections, bad battery terminal connections, Bad Converter/charger unit, Converter/charger unit 120VAC Circuit breaker tripped etc... are a few things that can keep you from charging your trailer battery.
Once you have the brand and part number of your converter/charger unit contact Randy at BESTCONVERTERER and let him identify the best converter/charger for you and hopefully it will be one that will fit your current install location.
Don't let Mr Randy sell you a WFCO product... Progressive Dynamics or IOTA Engineering are two great choices for the Converter/charger units. You will want to get a modern SMART MODE Converter/charger unit.
Depending what Power Distribution Panel scheme you have you may only have to replace the converter/charger unit and not the 120VAC/12VDC Power Distribution Panel.
Roy Ken
My Posts are IMHO based on my experiences - Words in CAPS does not mean I am shouting
Roy - Carolyn
RETIRED DOAF/DON/DOD/CONTR RADIO TECH (42yrs)
K9PHT (Since 1957) 146.52M
2010 F150, 5.4,3:73 Gears,SCab
2008 Starcraft 14RT EU2000i GEN
2005 Flagstaff 8528RESS