Yes, the engine alternator does charge the house batteries utilizing the battery boost relay and an oil pressure switch on the side of the engine block. When 15 p.s.i. of oil pressure is achieved the boost relay is engaged tying all the batteries in the coach together. The boost relay is what your dash "battery boost" momentary switch engages when held down; when your engine oil pressure reaches 15psi the relay engages as if you were holding down the battery boost switch. One should be able to see the house battery voltage rise on the inverter remote a few seconds after the engine starts. If the house battery voltage does not start climbing after the engine is started I would have a service center look at the boost solenoid and/or oil pressure switch that is added to the block.
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