RV battery maintenance
The 2019 Fleetwood Class A gas manual treats the house batteries as the reason the lights and most appliances work. Chassis batteries run the engine side. The two banks charge each other in specific cases: the alternator charges the house bank while you drive, and shore power or the generator charges the chassis bank. The battery cutoff on the monitor panel, also called Aux, disconnects house 12-volt loads. The manual says to turn interior lights off before you flip it.
In storage, the same manual is specific. With no shore power, turn the house and chassis disconnects off. With shore power, leave them on. Check voltage while the coach sits. A battery left discharged will freeze and be damaged. That is the warning in the storage chapter. It does not give a voltage number in the paragraphs this guide is based on, so none is added here.
The manual’s battery-maintenance and load-test details live further down Section 9, and it points owners to the OEM manuals in the owner’s information file for the actual hardware. Follow those for watering (flooded lead-acid only), torque, and replacement. Lithium batteries are sealed. Do not maintain them like flooded cells, and do not assume the stock converter’s voltages match a lithium profile. Read the battery sheet.
The Megawatt calculator’s smallest recommended floor is 1,280 Wh, which is its 12-volt 100Ah listing. Use the calculator for a size. Use the battery maker for care. If the coach is dark, the problem fixer walks the cutoff and the fuse panel before it suggests a purchase.