Great, long post with many pages of comments helping diagnosis electrical problem is here.
The below is a copy and paste of useful information, and I usually recommend it to those just starting out. Some of it, you may already know, or may not be applicable to your particular RV. You will be able to filter out what pertains to your situation or not. I would suggest you read the electric threads and energy management first, and then the converter thread. This will help explain your different electrical systems of your RV, and how they operate…as well as what the converter does. The very first link will explain what operates off what system.
Basic electric:
Basic RV Electricity – RV Information (RV Maintenance)
Your very important converter:
Converter or Inverter (they are different)
RV Converters and Amp Draw – RV Information (RV Maintenance)
12 volt DC:
12 Volt DC Circuit Breaker with Manual Reset
The 12volt Side of Life (Part 1)
Suburban water heater (if applicable to your RV):
Suburban’s electric switch and much more
Suburban Water Heater Video Guides
Water Heater bypass/crossover valves:
NO (OR LUKEWARM) HOT WATER -Please read first
And the newest additions to help understand what constitutes a true full cylinder in refilling vs exchanging propane cylinders… as well as how the automatic propane changeover regulator works:
Propane Cylinders (Refilling vs Exchanging)
Propane automatic changeover regulator
Inverters and residential refrigerators in RV’s: