This technical bulletin was created and published by Bosch Thermotechnology Corp. It explains how to flush and then refill the liquids in a solar thermal hot water heating system. Before beginning, the technical bulletin states that the work can only be performed when the solar thermal system is cool, so work should be performed when it is cloudy out or in the early morning. The bulletin then lists all the various tools that will be needed. The sequence of events is laid out, with details for each. The essential steps are: drain the fluid, pump and drain water to remove residue, refill with fluid, pressurize.
Author: Bosch Thermotechnology Corp
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