SunEarth DrainPack Hot Water Station is a pre-built tank assembly for simplified installation of a drainback type solar hot water heating system. All items are pre-mounted and plumbed to a SunEarth 80HE solar storage tank. Includes storage tank with dual wall heat exchanger, 6 gallon copper drainback tank, circulator pump, digital controller, domestic water expansion tank, domestic outlet mixing valve, bypass valves, and plumbed relief valve drains.