Heliodyne Helio-Pak heat transfer appliance for closed loop solar DHW systems that do not have a tank with an internal heat exchanger. Complete packaged pump station with double wall counterflow brazed plate stainless steel exchanger, Grundfos glycol pump, and domestic water loop pump, fill & purge valves, Heliodyne control with 2 sensors, pressure gauge, relief valve, & air purger. Expansion tank not included. Heliodyne part number HPAK 116-000.