I doubt both would work at the same time. I have seen that an inverter rated to X watts really won't handle that kind of an output for long. I use double the 1/2 the watts of the rating as the max usage. Additionally, how the inverter is wired will be a larger determining factor. You need large wires from the batteries to the inverter or the DC volts you are trying to suck out will over load the circuit. This all, of course, assumes that you have enough batteries in your coach to be able to handle a long term draw without dropping to an unusable voltage. Check the battery banks AH rating and add more batteries if necessary.
