Bosch AquaStar Universal Hydro Generator

The Bosch Universal Hydro Generator, part number 8707406104 (87074061040 or 8-707-406-104-0) is designed to work with all newer Bosch Therm 520HN tankless water heaters as well as all older model hydro generated units.  The universal hydro generator comes with miscellaneous water pipes, gaskets and bushings to adapt to the older units. The hydro generator works with water flow and has a small wheel that spins when the water starts to flow. The small wheel inside has a magnet on it that when spinning produces a certain amount of mili volts that is transferred through a couple wires to the ignition unit and that in turn lets the ignition unit light the pilot and then the main burner.  There is no need for any electrical power to operate the heater.

The older units that would require the universal hydro generator are the Bosch model 125HX, 425HN, 425HNO, 1600H and the Bosch WR400 series heater WR400-7K V1G23S3195.  The new universal Hydro Generator part replaces all older hydrogenerators such as 8707406043 (87074060430 or 8-707-406-043-0), 8707426026 (87074260260 or 8-707-426-026-0), 8707406059 (87074060590 or 8-707-406-059-0), 8707406069 (87074060690 or 8-707-406-069-0), 8707406095 (87074060950 or 8-707-406-095-0) and 8707406071 (87074060710 or 8-707-406-071-0).