The breaker is for the electric element which Aqua Hot tells you is for momentary hot water. For "endless" hot water you need to have the diesel boiler operating. Basically you have a Webasto that heats a large water tank within the AH (big copper coil wrapped around the tank). That's as basic as it gets! Keep the filter changed and use it frequently or you'll need a new nozzle every so often within the Webasto head.