Unless you've got something radically different than most, you should not have to go outside to switch the water heater to propane. On the face of the water heater, you should have a black switch. That's only for electric operation. Once you put it in the ON position, you don't have to ever change it, regardless of propane or electric. Inside the coach, you should have a red light switch (lower left corner of Master Control photo) that turns on the 120V electric for the water heater. And on your tank monitor panel, there should be a small red rocker switch with an LED light next to it that says HEATER. That switch turns on the propane. If the little LED is lit, the burner is operating. You can run the water heater on electric and propane, simultaneously should you want faster recovery. If you have switches like my photos, then what I've said will work for you. Just be sure your water heater is full before initially turning on the 120V switch or you'll burn out the element in a heartbeat.