Hey Pat - there's a section towards the back of the manual that talks about the monitor panel for the waste tanks. Not sure of the page number right now but I'll relay later when I get home. Read that section and you'll see it talks about all the switches on the control panel (pictures would have been good of course) including the tank monitor, the inverter control, heater, etc.. It states there that the heater switch is to turn on propane for heater. They certainly could have been more clear and included more photos like they did for the water control station. But hey - that's why we have this thread. Might be better to have a complete site for these units, but I'm of the not knowing in that regard. If anyone knows how to setup a website we could all put our 2 cents in.
