The person filling your propane tank should not care about any master shut off on your house batteries. If there is anything to worry about when filling the propane tank it is those appliances that may be close enough to the propane tank to give the employee concern when filling the tank. These appliances are the fridge, water heater, and furnace. The fridge and water heater have ON/OFF switches and you stop the furnace by setting the thermostat to the OFF position. Shutting them off kills any open flame that would worry the employee.
Are your house batteries located beneath the stair treads inside your coach door? Is there a battery disconnect switch hiding in there? Have you asked the seller if there is a battery disconnect switch and where it is located?
Was the RV's shore power cable plugged into a pedestal or outlet when you tested the systems? The converter can supply the 12V power to 12V lights and appliances when plugged into shore power. So if the 12V stuff runs when the shore power cable is plugged in but not when it is unplugged then start your investigation by looking at your house battery(ies).
Gain access to the house battery(ies) and put a multimeter on them to test the voltage.
Questions to answer:
1) are the house battery(ies) good? Do they hold a charge?
2) When plugged into shore power, is the converter charging the house battery(ies)?
3) if 1) and 2) are OK then you may have some other 12V electrical issue.
2005 Cruise America 28R (Four Winds 28R) on a 2004 Ford E450 SD 6.8L V10 4R100
2009 smart fortwo Passion with Roadmaster "Falcon 2" towbar & tail light kit -
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