Dry camping, batteries and slide out

I discovered two issues with my camper that were affecting my battery life. First my domestic refrigerator has a heating cable around the door gasket that runs off 12 volts continuously. It's supposed to prevent condensation around the door, but it consumes a lot of power. Second my WFCO converter will not go into boost mode no matter how discharged my battery gets. It always remains in adsorption mode which takes a very long time to recharge a depleted battery. If you have a WFCO converter you may have this problem too and therefore your batteries may not be fully charged at the beginning of your trip. I solved the first problem by disabling the heater cable. I solved the second by monitoring my battery voltage with a digital voltmeter and using an inexpensive stand alone charger you can buy in any auto supply store.